Id amc to chev trans adapter

I went out to look for but haven't found it yet but i believe it is 1971-73 like off jeep ster. I took it off a 1973 304. It has the 1 inch spacer for the crank and is cast and about 1 1/2 inches thick and uses alen bolts to attach to the amc block and a chev trans bolts to it. What casting number should it have ? Thank you all Dog.

Those were the heavy cast iron adapters AMC was using to adapt a TH400 to the AMC block... They were in Jeeps between 71 and 73 as I recall...before AMC paid GM to have the TH400 housing cast with the correct bolt pattern for the AMC block. You can use them in cars, but I don't know why you would want to unless you were going "low buck" for a 1971 tranny swap... The TH400 is arguably a better automatic than the BW-11/12 but starting in '72 AMC put the TF727 in the cars and it's a good trans. I wouldn't think it would be of any benefit to swap from a TF727 to a TH400... Both have excellent aftermarket support...

Bolt pattern on the torque converters.  they are different between the TH 350 / TH400...

That is an adapter to put a Buick Nailhead Turbo400 behind an AMC engine. Remember, this is a nailhead tranny, and NOT the same as a Chevy or BOP trans. The nailhead was also considered a universal TH400, as the bellhousing is shallow, and allowed for the thick adapter. Many different manufacturers used this trans behind different engines, with different adapters. Some of them were Rolls-Royce, Jaguar, and others. AMC even had the adapter to use this trans behind the Gen1 engines, as I have one for the 327 in my 66 Classic 770. That particular unit is from the Jeeps with a 327 Automatic.