63 Dodge Dart, now let me see;)
Your Dart has even tighter rear wheel clearance than the '67 - '69 Darts and those are pretty tight.
Here is a '67 Dart with 14 x 7 slots. With the 8 3/4 rear end. And the short big block leaf on the original leaf stacks.
Sold it to a guy I know and he had a slight rub when he put people in the back seat.
So as a precaution he put on the Monroe Max load leveler shocks for a safety barrier from rubbing. That took care of the rubbing issue, and still retained the nice ride.
Really doesn't take much air, like 25 psi or less.
☆☆☆☆☆