My "spatial memory" recall tells me a P245-R15 on your wheels should be fine up front, but P255-R15 up front might rub. Do a fit check if possible. Also, a tire dealer might not recommend the P255 for a 7" wide wheel. I tend to agree; and that's why I went with 15x8.5 on my first B body.
Below is my '71 Satellite with G60-14 on all four corners mounted on the factory 6" steel wheels. I recall those tires being close to rubbing on the front, but I never found any evidence of rubbing. I no longer have this car (GTX tribute, but some people used to say fake).
Below is my '79 Chrysler 300 (B body) with P255-R15 mounted on 15x8.5" wheels. All four corners. No rubbing anywhere...ever. However, I always thought the wheel wells on my '79 had more room than my '71. I could be wrong. I sold my '71 in 1980.
(More) Opinion time:
If I had a '71 again, then I would go staggered width front/back wheels so I could have a nice, wide footprint on the back, as well as fill up the enormous rear wheel wells. Up front I would go as wide as possible to fill up the wheel wells without rubbing. Normally, I like the same sizes on front and rear, but (again) the rear wheel wells on a '71 need to be filled up for visual appeal. Also, I would go with slotted wheels if at all possible. Just opinions...tastes vary.
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I know what I'm going to do when it comes to getting wheels & tires for my '70 Charger... I'm going to copy
@Kern Dog with adjustments for 3.55 or 3.91 gears.
