on a painted intake side of head i wipe clean with lacquer thinner then 2 inch masking tape. for intake lay a intake gasket use bolts to line gasket on head draw a line around gasket then cut with a razor knife peel off the tape off were you want painted. peel tape off when paint is still drying .less is better so you do not end up with a paint lip . etch prime just till you can not see threw it same with paint