Ah right the crazing,I used to do a lot of fibreglass work in the 70's cant anymore as its in my skin and I come out in a rash when I go near it

that said I do like it as a medium,
A lot of vehicles in the 50's onwards were made with grp bodies and composites of ally and glass.steel and glass and wood and glass to name a few,anyhows back to the prob in hand, when we got a vehicle in with the usual 'star' crazing, we would identify them all and run a DA over them first then I would use an engraver to erode away the flaky type material till I got back to a glass that was stillk relatively bonded and solid, this was repeated on all stars and any other surface cracks and such
next a thin coat of resin applied and overlaid with surface tissue, this was coerced into the depresions I had made, left to dry and a few days later sanded over, and left a week or more to cure, then prepped and painted in the usual way,
I will try dig some pickies out but they are 35mm so will copy and upload when I get time (need to do it anyway)
below is a picky of a Jensen 541, I bought this in the mid 70's as a mere 20 something

I will find the picks of the state it was in, any how the bonnet was the whole front and had been up and over on the A1 so I made it cosmetically correct, took a mould and produced the new bonnet/front, all the body was grp save the sills,door skins and lower front 1/4 panals, the grp was 5-6mm thick, this acr I remade the entire front from screen fwd and sills, this picky was taken recently and mailed to me by new owner, it lasted 30 yrs...