Chevy rear end ID help needed

I purchased a '52 Chevy 3100 short bed about two weeks ago. I have been trying to identify the drivetrain which has replaced the original pieces. I have been able to ID the engine which is a '71 283 small block and the transmission is a powerglide unit. The rear differential is still a mistery though I am ***uming it matches the other parts of the transplanted driveline.

The markings on the diff are -G116 (which I think is the date of manufacture). The other markings which appear on the front drivers side of the unit are 3707306 and GM15.

I have attached a couple of pictures of the unit and would appreciate any help the forum can provide in the ID of this piece.

 

57 Chevy p***enger car style pig, and 283's weren't in production after 1967.

 

It looks like a mid 50'sMay to early 60's Chevy drop out rear end.

 

Thanks a lot for the ID help.

 

date code says it's from July 11 1956. It's a Chevy car rearend.

 

picture of the crankshaft flange will id the engine. no such animal as a 71' 283 sbc. i had a 71' nova 4dr 307 and the casting on block said 61' 283 as gm used the leftover 283's for 307's