I'm looking at a rim 15 x 7 with only 4" backspace and 0 offset for the front of my 91 rs. I'd like a tire in the 225-60 range.
I know from searching that 4.5BS 0 offset would be perfect but they dont offer it...
Will this look OK ??
Where in relation to the lip on the outside of the fender might it be ??

 

4.5 is for an 8 inch rim. On a 7" rim, for it to sit in the same place, you would want 3.5" of backspace. 4" will work but they will be tucked an extra 1/2 inch.
I do believe 4"BS on a 15x7" rim is the same as stock 15x7" rims or pretty darn close.