Looking to fit the largest 15" wheel and tire combo out back on my '66 Coronet 440 2 door without mini tubbing. Trimming the 1/4 lip is acceptable. I currently have '78 Córdoba 15x7 wheels which I understand have a 4.25" BS. Tires are 245/60/15.

I've searched on the net high and low and found the following info:
-15x7 Cop wheels have a 4.5" BS and with 275/60/15 tires should fit. My question here, does it fit with low stock ride height?
-15x8 aftermarket wheels will fit with 275's if the BS is 5.5"
-Seen a couple of 15x7 American Racing Torq thrusts with 275/60's mounted. Confused as the BS is 3.75" on those wheels which would mean they would rub the quarter lip, correct?

Hoping for owners of these cars to chime-in and let me know their real world combo that actually fit.

I'm also considering installing Super Stock springs. Will I need C body shocks if I run those? I did on my '69 Bird.

Thanks in adavance!