Considering the New Model Single Actions and cylinder frames:
From 1972-73 forward the .357/.41Mag/.44Mag/.45 Colt were ALL on the large frame. The .44Mag is ALWAYS on the large frame (flattop, regular, Vaquero / Old Model or New Model) regardless of what you hear. The original Vaqueros were all on the same large frame. Then along came the New Vaquero and the flattops which are all on the medium frame. So that covers 'most' of the New Model frame variations.
Cylinder frames that I am aware of:
Bearcat frame (smallest) -- (.22)
Single Six/Baby Vaquero frame (small) -- (.22 and .32s)
Flattop BH/New Vaquero (medium) -- (9mm/.357/.44 Special/.45ACP/.45 Colt)
BHs and SBHs with ears, .44Mag flattop, and original Vaqueros (large) -- (.30/9mm/.357/.41Mag/.44Mag/.45ACP/.45 Colt)
There is one more frame variation, the .357 Max which I believe is an extended large frame.
Maybe others, but these are the ones I am familiar with.
When comparing serial #s, the medium frames seem to be stamped with 3 digits prefixs.