Spit Mk3 windscreen frame and dash top refitting

[Graham Ness]

I am about to refit the windscreen frame back onto my Spitfire Mk3 and plan to replace the damaged dash top cover, which was poorly fitted by someone in the past. The original dash top is still in place, but in an awful state. I will be leaving that where it is. 
Should the front edge of the new dash top cover be trimmed to sit against the back of the windscreen frame to scuttle seal, or should the new dash top cover sit under the seal? I have some DumDum sealing tape which I plan to place under the seal/on the scuttle top to try and make it all water-tight.

Any wisdom from others who must have already done this would be appreciated.

Thanks.

[Colin Lindsay]

Gt6 Mk1 shouldn't be all that different; in my case I fitted the screen frame first and tightened down onto the seal, then fitted the dashboard afterwards. So: in my case at least the dash cover was not under the seal which is what it says: a seal between the two metal surfaces so presumably should be left alone to do just that, with nothing underneath or above that may prevent a seal. It's really up to yourself as to whether it matters, or with regards to the excess; can it be folded round behind the dash rather than trimmed? I'm always thinking of the 'just in case' scenario... but if it was me I wouldn't put it either under or above the seal.

[Graham Ness]

Thanks for the response, Colin.

The dash top cover is several mm thick, so will need to be trimmed rather than folded.  But, having slept on the issue I think I'll try to go with your approach.. tighten down the windscreen frame onto the seal, cut the new dash top to fit behind the frame and seal and secure it in place with the three bolts and cover/attachment plates (611669 - Spitfire uses these, I don't think GT6 does) that secure the back of the screen frame and seal.

Clearly the rubber seal is meant to do just that (seal), but did you use any sealant between the scuttle and the seal, and between the seal and the windscreen frame?  I had planned to run some DumDum (Butyl) tape sealant between each.. but am I just being neurotic about water ingress at that point?

Hopefully a job for this weekend.  Thanks again for any and all input.