soda blast then paint?

Hi.
81 550 LTD motor. I plan on pulling it out of the donor bike and putting it in mine. I'd like to paint the top end and lower end, with the exception of the clutch cover, stator cover etc, which will be polished.

I've done this before with just simple green, a tooth brush and some cuss words. But this time around I was thinking of a simple green bath, some scrubbing and trying the soda blasting. Would I need to sand the original finished some, or think if I soda blast it it'll be good enough to toss paint right on? I was thinking I'd sand the smooth portions (like the lower end and the cam cover) but the fins and such have a rough finished to them already.

Also, will soda blasting remove the original finish or just clean it? (I believe its silver powercoat).

Soda blasting should remove paint. Justs takes awhile as it's a soft media. Remember to mask every opening then go back and look again, don't want anything getting inside. Wash throughly. Use quality primer and paint. Head and block should not be powdercoated as it acts as an insulation trapping heat. I don't think the factory used powdercoating back then any way. Good luck with your project.