AJ, according to the parts manuals – there are 4 different K-frames for all FMJ’s, two each /6 and 2 each small block - with a few minor differences between the years. The engine mounts are in different locations on the K-frames between engines. The other difference is Police vs. non-police.
I have sat a police K-frame up against a non-police – and I can’t detect any differences between them. Maybe thicker or hidden welds – IDK. I didn’t weight them.
My opinion: there are only two different K-frames (/6 and small block) – and factory parts book shows otherwise.
The year of production - I hadn't seen any issues on interchangeability between the years.
I was told by a Chrysler factory rep, the torsion bars are all the same – except between Left and Right. The differences are the bushings, with HD and police bushings being firmer rubber.
With as many part numbers on the books on torsion bars – I wonder about that, but my measurements on several torsion bars, including police, have all came to same readings.
I didn't know any of that, but had drawn similar conclusion from both internet chit-chat, and a small amount of experience.
And I had confused same T-bars for same Ks. So thanks for clarification.
As always, your eye for details is amazing