engine plate coatings ?

[Charles.]

Powder / plastic coat [perhaps too soft & will dent].
or stove enamel [crack, flake or chip where gbox tightens]. What was standard finish?

[Rohan B.]

You don't say what year and model, but the original finish was almost certainly stove enamel. Used engine plates always have the finish worn away around the gearbox mounts, and indeed around most stud holes. So it doesn't really matter what finish you use, it will wear away too, same as original.... A little paint carefully dabbed on will disguise it, to keep that "as new" look, if this is important.

hopethishelps,
Rohan.

[OEW591]

I have used two pack enamel, hand brush painted enamel and powder coating and have found the powder coating to most be durable BUT powder coating does increase the thickness of the plates and therefore everything becomes a tight fit especially if you have powder coated the frame too.