79 malibu wheel width fitment

[79 malibuls]

I’m looking to get a new set of wheels and tires for my baby girl. Was wants to see if anyone knows the widest tire I can tuck into the rear without mini tubs.was wanting to run 28x12.5x15

 

[michmalibuman]

I'm running 15x8 on the rear with 275/15 on my 80.