Having taken the bubble wrap off the screen for the first time I realised how careful I had to be. The windscreen was very shiny, sleek and quite heavy, but it was manageable for one person to lift in and out of the stanchion holes. And fitting it did turn out to be quite straightforward although it did take a couple of days, and there was a lot of head-scratching and contemplation sessions. This was because I realised that I had to get-this-in-one. It has to be done properly and with precision i.e., I couldn't mess this up.
Alignment: Having first drilled and dressed the two bodywork stanchion holes, I offered up the screen to see what I had to do to make it fit perfectly. Essentially I needed to line it up with four reference points before drilling the brass uprights:
- 1st Reference Point: The top centre point of the windscreen (the rake angle.) This being the distance between the top of the back of the cockpit and the top centre point of the windscreen. The requirement is 930 mm.
- 2nd Reference Point: The 6 mm gap at the outer edges of the screen
- 3rd and 4th Reference Points: These were a bit more challenging because I had to ensure that both the top outer edges of the screen were equidistant to "somewhere."
Reference Point Positioning Procedures
1st Reference Point: For this I used a wooden spacer taped in position, having first put some insulating tape on the car and screen to protect the gelcoat and chrome. With this wooden spacer securely in place, the screen was now well supported and I had my first reference point sorted. I did at this point, step back to see how the screen looked without me holding it... Awesome!
I put some masking tape on the inside of the stanchion legs and cross-haired marked where the ~2 mm factory drilled, pilot holes were. This for me to see how far out the pre-drilled pilot holes were with respect to my own measurements. And I was pleasantly surprised to find they were very accurately drilled. However, they were not quite on the centre-line of the stanchion legs. They were all off-centre by 2 mm. But as everything lined up I thought there was some engineering logic going on that I was not aware of. So I left it at that.
I re-verified the 930 mm windscreen rake angle spacing and then fiddled with the stanchion legs to locate the top screw holes. Lots of thought processing and jiggling going on and I was getting nowhere fast. And this was because the small pilot hole could be wiggling around anywhere within the 8 mm captured body holes that the screen was to be bolted to... So, tea time again.
Being suitably refreshed, I decided to drill out the 8 mm top [pivot] hole of each upright and temporarily bolt the windscreen in place. My rationale being the top bolt hole is the pivot point for everything else. An hour later, holes were drilled and the windscreen was fitted and bolted in place (hand tight only)..... So far so good.
Now I had to work out where to drill the bottom stanchion leg bolt holes. I could have just opened up the lower pilot hole to 10.0 mm and whittled away until it looked okay, but that would have been too easy. Don't know what it is but some things just have to be done the complicated way. And in this theme, I wanted to have the two 8 mm holes be where they were supposed to be without any whittling. No one would know - but I would... This job had become personal.
Continuing, these two drill holes are probably the most important points because they play into the hood tensioning arena and I don't want one side being floppy whilst the other being too tight.
2nd Reference Point:I straightened out the rubber seal on the scuttle top by pulling it from the front and pushing from behind. This to make the windscreen sit as best it could and for me to see how accurate the required 6 mm gap was... Spot on! Nothing more to say about this.
3rd & 4th Reference Points: My "somewhere" reference points were going to be to the corner points on the bodywork where the door shut and the centre of the top windscreen retaining screw. The initial measurements for these from the door point of reference were 74.3 cm on one side and 76.0 cm on the other side... Not good!
Having had another good think and another session with the teacup and tape measure, I discovered I needed to elongate the body stanchion holes. The issue being I hadn't made one of them long enough for the screen to angle back enough. Note... My GRP cutting theme has been to cut small and expand. Nothing wrong with this strategy as I'm not a fan of repairing gelcoat through being impatient or trusting of any markings.
So screen out again and Dremel in, and an hour later I had enough room to jiggle the uprights to get them both exactly the same distance from the "somewhere" reference points; each being 75.4 cm. Then I cross-haired marked the masking tape where to drill the lower 8 mm holes. Dismantled the screen (for the umpteenth time) and drilled the M8 holes... Result. The screen remained centred at 930 mm and each end was equidistant from the reference points.
Caution thought here: Knowing the screen uprights were brass, and therefore a soft metal, I realised, because I didn't have the dash' cross-member or steering rack support brace in place, if I tightened up the windscreen bolts without packing out any horizontal slop I might be putting undue pressure on the screws that were fixing the screen to the uprights. i.e. It might cause distortion and therefore unnecessary strain on the brass threads. So I just tightened up the bolts to a point where the screen was gently but firmly supported. I'll take care of any horizontal slop later on when I do the final fitting.
The job is looking good so far..... can't do any more at this stage as I have to drill the demister vents. Couldn't do it before as I wanted to see how they would look with the windscreen in place -before I drilled the slots out. So, with the windscreen in place, I placed the chrome demister escutcheons on the scuttle top to see where to drill the slots. That being, I needed to ensure they looked good and proportionally placed with respect to the screen... More on this later.
Bent the escutcheon to shape and will polish and fit permanently at a later stage
Mirror Bracket: This took an absolute age fit. The unit is in two parts, and because I wanted a neat and shiny top edge I decided to put the upper angle bracket on top of the bracket that is secured to the scuttle top... So because of this, the bottom bracket position had to be positioned 2 mm back from where it was supposed to be. And now the pre-drilled holes that take the two 3 mm screws to tighten everything up were in the wrong position. They were now too high up. So, as I had to move the bracket 'further back' I had to move the holes. But I couldn't for the life of me work out if I had to drill the holes higher or lower... Some head-scratching and a cup of tea later, I made a drawing of what I wanted to do and put some reference lines on it to work out what which way to go. Here is a short video of Bracket Drawing to illustrate my dilemma and solution.
After a lot of measuring drilling and filing, all fitted very well, and I have a nice neat top-edge to the centre mirror bracket that no one will ever notice.
I'm not going to fit the screen permanently yet as I still have to polish up the windscreen escutcheons. Also, the dash' cross member and steering column support bar have to be checked for slop. When all this is done I will silicon-seal the windscreen holes and fit everything forever.