If you do polish that frame, you will need a clear coat of some kind.
The TM pot metal, unlike aluminium, will tarnish to a darkish grey very quickly even after polishing
Polishing from a sand blasted state will take a fair amount of work.
Slightly different metal, but for my P229 slide after sand blasting, I wet sanded by hand with 400, 600, 1000 & finally 2000 grit followed by Mother's Aluminium Polish. Still gets a little tarnished, but a small buff with some polish takes care of that.
Did the same process on my Franken capa slide.
