spacers and shims? or arch work?

[deanpompey]

so am currently a 70/60mm drop, on ATS cups with ET20, and 195/50/15's. I put a set of 20mm spacers on rear to bring it out to ET 0 and love the look, but am catching the arches quite badly. have already taken the lip off the arches with a grinder, have about 4mm clearance at standstill, but soon as i move off they rub. was wondering if camber shims may sort it? if so how much would i need??
dont want to run stretched rubber as tyres are brand new parada s2's.
other option i thought is to remove the arch trims, take another few mm off of them so theres literally nothing but the edge remaining and hammer the arches out then bond trims back on?

any ideas/thoughts?

[Wayne]

Why not switch back to 10mm spacers.

[Ben Lessani]

Get the arches rolled, fit some shims and fit some 30mm spacers 

[deanpompey]

because they look awesome with 20mm spacers! anything less wouldnt be worth doing now iv seen them at ET0.

im gonna chop the arches if i have to, was just wondering if using shims would give me enough clearance so i didnt have to!

if not, the grinder will be coming out.

so back to my main question, can i use shims with 20mm spacers, and will they clear the arches without having to chop em up??

cheers