We have them on one of our cars. Just put them on.
Be aware that you may have runout issues with them and also may have a difficult time to balance them.
check out this thread, it may help you.
http://www.forabodiesonly.com/mopar/showthread.php?t=114416
On our 71 Scamp we have the 28x12.5x15 ET Streets and they clear. The car is mini-tubed with inboard springs.
We just took off a set of Sportsman Pro that had a section width of 13.5 and 29" tall (approx., can't remember the exact section width but very close to the 13.5") and they rubbed when going around corners or if somebody was in the back seat of the car. The inside of the wheel well has a kick-out portion that hit the tire. If you have the same thing flatten it out. Also roll the wheel well lip, you will need it. The tire was also rubbing on the inside up against the fuel line that is attached to the frame on the drivers side.
onig