I wouldn't shave anything. You can buy 2.5 mm spacers from Z1 and probably other places. Even if you have to buy longer studs, it's totally worth it to not take the ghetto way out.
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Competition Clutch|Fast Intentions|Maxbore|NST|Setrab|Stillen|Tomei|Uprev| Z1
Avant Garde|SPC|Stance|Whiteline
Aerojacket|Seibon|Tanabe|TRS|TWM
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