I have had proxy 888 on a 10.5 inch rim in 305, 315 and 335 wide with HR race springs and 3/8 inch spacer and low pro IRS bolt with no issue and no fenders rolled. 335 had to much bulge IMHO, but the 305 and 315 proxy 888 fit just fine.
I had the 315s my car has HR race springs no IRS bolt but it was really close to it! and as mentioned previously when hitting and unexpected dip I would scrape a little.
