As long as it’s a thicker area and I can put a 3/16” straight through to the combustion chamber them drill and tap a 10-1 mm thread for the cr. The through hole needs to be smaller than the cr valve itself Incase it broke it can’t get into the cylinder.
Turns out the open space between the top fins is tough to squeeze in a cr. I found out with my next cr project I can angle it like a 570/576 has on the 2100.