Allow 3mm glass to recess a little further.

Door and front windscreen rebates were designed for older 2mm plexiglass, but we have the newer 3mm plexiglass.
With gelcoat removed will allow 3mm to recess a little further but probably will still need a little fill to make it flush. We plan to put a thin model aeroplane ply on seam to help prevent later cracking.
Y9-06-27