255/60/14 3,55BS, will they fit on my '72 swinger?

I have 2 69 dart swingers with no rear diff or spring location modifications.
1 has 255/50R/17 with 4.50 BS and they are tight fit in the wheel wells about 1/8 clearance to the quarters and about 5/8 clearance at the springs
The other has 255/60/15. (They are actually 28"x10x15" M/T SR radials pretty much the same tire only a little taller )went to 4.75 BS and they are pretty much centered between the spring and quarter panels about 1/4 to the quarters and 3/8 to the springs.
So without seeing whats going on in the back of your 72 (Dont know 72,s that well),it should,nt be that much different than a 69 ,there is no way a 3.5 BS is going to put the tire in the middle of your well, it will most likely stick out past your quarter.
Every car is a little different so maybe this will help you as a guide.
Good luck.