UBETRUN

After a few years of upgrading the motor, trans, rearend, suspension, brakes, steering, cooling, fuel, brakes, etc., this 1970 is back on the road. I do not like the current wheels/tires and am looking to upgrade. I have read the wheel/tire threads and the fender flare threads but I don't know if Motion flares are L88 flares and even if they are, it seems that no two fender flare installs turn out exactly the same. The rear is a little too high now with stock spring bolts so I will have some 8" bolts on hand when fitting the new shoes. Rear rims are 15x12 with 4.5" BS and the front rims are 15x8 with 4" BS. Using the current setup as a baseline, what are some recommendations for 17" or 18" wheel and tire sizes? And pictures of any suggestions are greatly appreciated!