offset mounts and tire size gain?

Does anybody here have any pictures or info on the offset spring kits which move the springs in the 1/2". I was wondering what I could stuff under there in a 17" or 18" tire/wheel combo to fill the void. Also, does the kit have any effect on the stock exhaust pipe routing? I have my 8 3/4 on the bench now and am wiating for the new Espo springs to arrive. After all the work on rebuilding the rear, I was thinking if the net gain to move those springs the 1/2" would be worth doing while I have the rear end out. Any help on what you have and sizes of tires/wheels on a Demon would be of great help. Thanks in advance for the help.