Hi. Since my GRP parts were in a sorry state, I decided to fix the crumbled gel coat with body filler and cover the body in vinyl. I went for the premium film, Arlon Ultimate Premium Plus in Hornet Metallic. It's an air release film that has a microscopic pattern on the glue that allows to squeeze the air out of trapped bubbles. 7x1.5m were enough to cover the nose, bonnet, scuttle, wings and arches.
I botched one 1m length while doing the bonnet. The glue is meant for auto paint, it sticks too well to aluminium and I managed to delaminate the gold layer of the film from the clear when peeling the film from the bonnet. Also I burned through the film with a heat gun in a couple of places. I just cut out the damaged area and stuck a patch on top. It's not pretty up close, but does not stand out.
The film is not completely opaque, there's a subtle colour difference between the bonnet, where there's alluminium beneath the film and nose/scuttle. Some of my fixes have the original yellow gel coat, clear resin on the repaired areas and white body filler, and all these shine through. So for the remaining parts I sprayed the repair with a nearly matching colour before wrapping.
The manufacturers of the films provide plenty of instructional material online, e.g.
http://www.wrapitright.com/
In retrospect, it was a pretty time consuming job. A rear arch is about 2h, the nose about 4h of work, so in total it took about 20 h. It's pretty hard to wrap complex shapes without any defects, I left some minor wrinkes on the sides of the nose cone, also, caught some debris beneath the film in some places. Despite that, the general look is pretty good.
https://goo.gl/photos/TTTSTUTbMcmbWViA8