I've painted many brass engines over the years. I have read and talked to others about stripping the lacquer finish and most all agreed that stripping is not necessary unless the clear coat is pealing.
If the clear coat is well applied, just give it a good wash and apply a primer undercoat. Let it dry thoroughly, I usually wait at least 24 hours.
I still have the first engine I ever painted back in the 1970's. The paint has yet to peal or chip, even though I ran it a lot.
The one thing about stripping the clear coat, if you don't get it all removed, you will have some issues that could result in pealing.
Ray
