hi guys after a couple of years of pondering this idea i decided to bite the bullet and do it
i fiberglassed a commodore one before but that was easy so here is the write up for this mod
step 1 find someone who will let you chop the roof of thier datsun (thanks hyflo)
step 2 fill the roof cut with expanda foam
step 3 carve and sand the foam untill you get the desired shape
step 4 glue aluminium foil to foam use 4 of 5 layers overlaping as this will help breaking it out of the mould
step 5 lay choped strand mat over foil
step 6 soak the matting with laminating resin and wait 4 the magic to happen
depending on how much hardener you use you may be able to remove from the mould in 2 or 3 hours i trim the edges at this stage and leave it in the mould overnight
step 7 using wedges and compressed air remove the item from the mould
step 8 sand the new fiberglass roof smooth it will need more sanding to paint than it will to trim in leather