the only problem with gelcoat is getting paint to stick to it, use a fairly rough grade of sand paper to rough the whole lot up,
you might find primer advertised as good for use on fibreglass as opposed to steel, that'll help
put 2 or 3 thin coats of primer on, sanding between layers and then go from there
you might find primer advertised as good for use on fibreglass as opposed to steel, that'll help
put 2 or 3 thin coats of primer on, sanding between layers and then go from there