I went through the same thing, with a '66 Satellite. I minitubbed it, to the frame rails, and was able to get a 15X10 wheel with 7 1/2 backspace and a 29.5X11.5X15 M/T ET Drag to fit, with an inch of clearance on bothe sides of the rim with a stock width (59 1/2" 8 3/4) This was with SuperStock springs moved into the frame rails. I went to the Caltrac setup, but found it inconsistent in the 60's, I was never able to tune the launch properly. It would sometimes leave perfectly, then the next run it would bounch the back end. 60 foots were in the 1.50 or worse range. Looking back, it was probably the Rancho shocks. Out of frustration, I converted to ladder bars, and what a difference! It now will hook, lift the front wheels, and 60 foot the same run after run. My 60's are usually 1.40-1.42. This year, I moved up to a narrowed Dana (51 1/2") and used 15X10 wheels with 3 1/2 back spacing. PM me if you want more information, hope this helps, Bob