Ah, good spotting, I see the same thing in '65: 1613 TA7 for all Darts and Valiants except convertible, 1614 TA7 for convertible. Your 1648 BX7 does show up in '66 for Valiants, while Darts continue to specify 1613 TA7.
Dan! In that case my friend Johan must have a 66 Valiant trunk mat. I'll just switch the numbers to 1613 TA7. Thanks for the help Dan! I need to get some new potatoes.......:banghead: