Input on Slick size for 72 Swinger

Looks like I missed the 28.5" deal, hav e to buy 28" off Jeg's now.
http://www.jegs.com/i/Goodyear/478/D2791/10002/-1


Might be, they were on the car when I bought it, 6 leafs. My 255's are 10" wide, but 27" tall, the slicks are 10" x 28.5.....hmmmmm. More air in shock. Or roll the wheel well lip.