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

I know, i have another thread about if my centerline wheels would fit, but the bolt pattern was all wrong :( So i was wondering if 14", 3,55 backspace and 7" wide rims with 255/60 tires would fit in the rear without major modifications?

Wheels with this bolt pattern are extremely hard to find here in Sweden, so i was thinking about making my 5,5" plate wheels 1,5" wider so they will be 7" wide.

Anyone running this combo? The part im figuring most over is if 3,55 backspace is to little backspacing?