Three types of drawing numbers on IHC rifles:
IHC D6528290
6528290 IHC
and 6528290 IHC over a single letter.
Garands that were originally converted to 7.62 NATO had a plastic block installed to keep anyone from putting a 30-06 round in them if that helps you any.
Just for info, those short barrelled "tankers' kick like a mule and have a muzzle flash like a barn on fire which is one reason that Springfield decided not to make a short barrelled Garand..also the original tests were not to make them for issue to tank crews (they were mosly issued the 45 cal M3Submachine (Grease) Gun, cheaper to make and took up alot less room than even a short barrelled rifle) but rather for issue to paratroops since there were some complaints that the m1 carbine round lacked stopping power.
The short garands can be fun to shoot but just something to know if recoil is an issue for you.