Welcome in Eric.
Sandblasting an engine is alot of work. To do it right you would really need to completely disassemble everything so that you could get it cleaned up properly afterwards. Those little bits of sand will get everywhere.
I sand blasted one of these engines and got it all cleaned and flushed out in my bathtub.But it look a lot of time and I had to source a lot of different brushes and pipe cleaning tools to get all the passages scrubbed clean.
It's totally doable,but you won't catch me doing it again.
Sand it down by hand and paint her up. It's gonna get covered with mud,bugs and rock chips anyway.
Good luck on your bike. Keep us up to date on your progress,too.