I have a 1956 Crown Victoria that have 670 x 15 bias ply tires with Thunderbird wire wheels. I need a new set of tires and would like to change to radials however radials are a much wider tire than what I have now. All the tire conversion charts says I could go with the 205x75x15 radial tire. The 670x15 are 7.01 inches wide and 28.88 inches in diameter. Most 205x75x15 tires are 8 inches wide and 27 inches in diameter. Although my shop manual specs are 710x15 for v8 Fairlanes with Fordomatic, I can't because I have Thunderbird wire wheels and their specs are 670x15.

Here's the rub (no pun intended). I only have about 1/4 inch clearance between my existing tire and the upper control arm ball joint area. Going from a 7 inch wide tire to an 8 inch wide tire, in my view is not going to fit. Can someone tell me what the gap clearance between the tire and upper control arm is on a 56 Ford with stock rims? Is there someone who has Thunderbird wire wheels on a 56 Fairlane or Thunderbird and went with a larger radial tire and had any problems? Are wheel spacers reliable - I don't know anything about them?

Thanks
Danny