I spoke to the guy that owns this car and he is running G60-15 on the front and L60-15 on the rear on Rallye 15 x 7 rims with standard backspacing and no suspension mods.
He also has these for the car; Goodyear Eagle 1 yellow letter tires (245/60 front, 275/60 rear).
Looks like my tire combination will work. I checked and the 15 x 7 rim is ok for these tires but I think I will go 15x8 on the rear. I was going to try to fix the rolled rear fenders but I may just leave them as is and it should give me adequate clearance. The L60-15 has about a 10 inch tire width.
Ran numbers with the 4 spd, 4.10 rear and with this tire setup the rpm at 70 mph would be 3443. With the GV it would be 2685 rpm and 2754 rpm with the Passon Performance 5 speed. With overdrive the rear axle is equivalent to 3.23.
Only decision now is whether to go with the GV and the A-833 tranny which would be like a 8 spd if you shift in and out of OD for each gear. GV makes a pistol grip with the OD button on the grip so to go into OD is just a push of the button. This would be the gear ratio for the tranny through the gears and the rpm's the motor would be turning using the GV.
2.65 1st 40mph @5200 rpm
2.06 1st OD 50 mph @ 5050 rpm
1.93 2nd 55mph @ 5200 rpm
1.50 2nd OD 69mph @ 5100 rpm
1.39 3rd 75mph @ 5100 rpm
1.08 3rd OD 95 mph @ 5050 rpm
1.0 4th 102 mph @ 5000rpm
.78 4th OD 131 mph @ 5000 rpm
In theory I could do 0 to 60 in 1st gear and turn 6000 rpm without having to shift.
The Passon 5 spd would have the similar numbers for 1st to 4th above and in 5th at 131 mph 5150 rpm. It has a .80 final in OD.
The GV setup would be about a 2k savings. Going to have to think about this some more. There are a lot of pro's and con's for each