I'm planning top seal some exterior cabinets with Helmsman oil based spar varnish. I'd like to topcoat with an oil-latex paint to match the existing shop exterior. Has anyone tried this? Would I need an oil primer or just scuff the spar varnish before painting? I'm concerned about the paint top coat alligatoring/cracking.
The cabinets hang on my exterior shop wall and will be exposed to seasonal snow and rain.