Yeah it’s not so much side to side as it is front the back. If you look at the second photo you can see the front hole it looks like it should go into. Looks about an inch back from there.
Picked up a 1978 Chevy K20 a few backs back and just got back from a 300 mile weekend driving it and noticed the crossmember bar bolts had come undone on one side. Previous owner put a 5.3 LS with a TH400 trans in. Jacked it back up into place to replace the bolts and it doesn’t line up with the...