spray is the only only way IMO, sandblast it, but remember to either take out or tape up the steering bush and bearings in the swingarm and a-arms.
Do a etch primer, 2x coats, then if you go base coat followed by clear coat in the case of metallic paint, (not recommended) only one coat of base coat is needed.
I prefer to use a 2K (epoxy style) silver paint, mix in hardener at 2 parts paint to 1 part harderner then use 2K thinners to correct consistency.