Going to start on the interior fibreglass surfaces of our 73 Boler (as yet,un-named, but, due to what is happening to it, I've come to call it "The Toolshed"!) and wonder what surface treatment others have followed. Right now, we have that lovely green colour that along with Harvest Gold, was so popular back then. We want that lovely green GONE.
Suggestions, please?

Wash surfaces to be painted with TSP, then scuff (sanding really not needed) the f'glass, wash again with a de-greasing cleaner, paint a primer /sealer coat with a foam roller and foam disposable brush (to avoid possible lint and bubbles made with a matt type roller). Lightly scuff the primered surfaces (wash/degrease again to get any possible particles or grase from the f'glass) and paint (with foam roller an brush) with your choice of paint. There seems to be a few different 'camps' as to which paint is best!! A second (possible) coat could be applied if you decide but there again, I'd lightly scuff down the glass before second coating....
....just my 2 cents worth!!

Spraying with a two-part LPU would probably be my first choice.

If you are going to brush your own, I have heard good things about the Melamine paint available in Canada.

I would suggest solvent washing as the first step (before sanding or scuffing). Mold-release wax should be removed from the gelcoated surfaces (it can hang on for 40 years, unbelievably) prior to prepping.

Interlux 202 Solvent Wash is one product that can be used. The main thing is to use lots of clean towels, and keep folding and re-using clean sides so as not to spread contamination that you are trying to remove.

Raya

Thanks to you both for the suggestions!