Best I know is in Kulick and McKee's
The M1 Garand Complete Assembly Guide, available from Fulton Armory at:
Fulton Armory: Fulton Armory Library
(That's a book; don't know of any web-based publications. Truth to tell, I'm not too sure I'd trust 'em, anyway!)
You do, however, want to very
very very careful not to get the trigger hooks stoned down too much, nor to get the trigger pull too light. Don't let the pull go below 4.5 lbs., and 4.75 lbs. is even better to allow for wear. If you go too far with "smoothing" and "lightening" ol' Betsy will most likely at least double, and may fire off a complete clip of eight in sorta-kinda full-auto mode. Not a good way to become popular with Range Safety Officers!
Ben Hartley