Correct Heel Pad on Carpet?

[quapman]

I have two carpets and need to choose the right one to go in a 73 cuda. One has a rectangular heel pad with grooves. The other has a heel pad that's notched...kinda looks like a 727 tranny pan. It has grooves front-to-back and on the right, a section of side-to-side grooves. Memory says the rectangular pad is 70 only, the notched pad is 71-4, but my memory has failed me too many times lately.

Pics of ORIGINAL cars carpets' would be awesome.

Thanks!