I have been happily building up the arches on my live axle fury body to take IRS with 7" rims and now have a satisfactory shape.
https://picasaweb.google.com/102680160261680183167/FuryRebodyOfLocostChassis#slideshow/6248189134072169762
https://picasaweb.google.com/102680160261680183167/FuryRebodyOfLocostChassis#slideshow/6248189133268548482
Started off with expanding foam trimmed down, thin layer of fibreglass so it holds its shape then filler on top (quite a lot).
I,m planning to run a second coat of fibreglass on top of the filler, couple of layers then tissue coat, does this sound like the right thing to do as
it gives me the option then to grind away the layers of filler, glass and filler?
[Edited on 7/2/16 by mark chandler]
If you have the shape you like why not make a mold of the wing extensions and make new extensions to fix to the car wings that way if you damage any
you have a mold to make a new one
jacko
Fibreglass is amazingly expensive in small quantities, once made if they get snapped off I will stick them back together again.