I'm buying new wheels for my 70 Satellite, for the rears i'm a bit unsure what tyres to fit

I'm getting 15 x 8 for the rear but they have a 3.75" backspace, ideally I would like 275/60/15 but do you think that size would rub ?

The fronts i'm going with 15 x 7 with 225/70/15 I think, also 3.75" backspace, think that should be ok ?

Many thanks.