Yes you are correct. Cases came in a natural finish. This one was stock except for the front master cylinder to brake hose and the battery side cover (that wasn't an option till a couiple years later).

 

 

How about trying paint thinner first, or maybe Acetone or MEK. If none of that works then it means pulling the motor and taking off the carb (use rages to block off intakes). But I am thinking a good bead blaster could tape off most of the top end and exposed cone and motor sprocket side? Seems like something like bubble wrap and the packing wrap that reminds me of Seran wrap could ensure that nothing gets in your motor. Not a lot of surface area that is painted

 

The transmission case on my Flathead had been painted black somewhere in it's life. Real thick crap, very industrial. It took some time but using Aircraft Paint Remover I got it all off. Spray it on, let it bubble, then light scrub with a soft wire brush. Repeat as needed to get it all off.

Could it be done in the frame? How much patience do you have? If you pull the motor I bet it wouldn't be too bad to do on an engine stand and save yourself pulling the entire motor apart.

https://www.autobodytoolmart.com//kl...CABEgL_X_D_BwE

 

by the time you strip the motor down enough to remove all the paint, you're five bolts away from pulling it. and you don't have to worry about accidentally getting paint stripper on your frame. motor stands are easy to make: