15 inch steel wheel measurements

I know for a fact that 255-60-15 will fit... i had it in there before upgrading to bbp ... I had it in there with custom made stockton wheels ... center was sbp on 15 in ring.... no rubbing at all... now that i upgraded i was just wondering what and if guys could fit an 8 inch in the rear with 255-60-15 tire .... and it can be done as per abve ... my advanatage is that i can have stockton locate center in ring in any spot to accomodate clearance issues ... HOPEFULLY .. thanks