Big block A body spool mount K member?

I recently picked up a '68 Cuda FS 340 car. The car was out in the woods, but I met the owner. He says he put a 440 in it back in the 80's, and spun it out on black ice crushing in the quarter. Anyways, could anyone tell me what this K member is exactly?

It's an A body K member, but it appears to be spool mount ('73+) but for a big block. No big block in an A body after '69. What do I have?