Um… buy larger wheels with the 4 x 4.5″ bolt pattern.
Wheel Vintiques sells new 15″ wheels with that pattern. Many cars used the 4 x 4.5″ bolt pattern, including six cylinder versions of the early Falcon, Comet, Mustang, and Maverick. I have 14″ aluminum slot mags on my 62 that were originally on an early 60s Mustang. FYI, the Mustang II and later Mustangs do NOT use that same bolt pattern and those wheels do not fit.
I have Wheel Vintiques 15″ smoothies in the 4 lug pattern and run 205 65 15s, American Racing also sells a selection of alloy wheels in the pattern. You may want to consider 16″ wheels for more tire selection as we move on. 205 60 16s are about the same diameter, still have a “vintage” sidewall, and there are a ton of them available.
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