Glad you posted a picture with the last three digits/hand written part number visible.

The problem is, assuming the "456" is correct, then those are the wrong leaf springs.

I've tried to install them myself on a 68 to 70 b body, with the same result.

456/457 are too short, and they have a 35 inch rear segment, Mancini's website has been wrong for years.

You need leaf springs with a 36 inch rear segment.

Only two Mopar Performance springs have the correct 36" rear segment length: P3690455 left, and P3690454 right.

If you have your heart set on the 456 and 457 springs, you can make them work but you will have to
punch a hole through the frame rail and weld in a tube forward of the original location.

Good luck! up








Before it starts-
no, all super stock springs are not the same
yes they all do have a 20" front segment length
no they do not all have the same rear segment length
no the front hanger doesn't make up for the different rear segment length, only front where applicable

Rich H.

Esse Quam Videri