[Shotimes] '89 SHO - fender lips cut, stock slicers, 225 55 16's still rub?!

[Neno Albert]

This is totally driving me nuts! Why is it that my '91 would have more then enough clearance for a
225 55 16 Yokohama AVS Db, yet my '91s replacement (a '89) will not stop rubbing in the back?!
Both have eibachs with tokico struts but otherwise stock. I cut the lips to the point where
there's nothing left of the lip!! I even went through the trouble of  cutting the lip down even
further down then where the tire can contact the fender just for some peace of mind yet it still
rubs... The only difference between the two cars is that the '91 had the stock canadian rims and
the '89 has the italian slicers... Was the back spacing/offset different at all on the rims? Is
there something with the setup i'm overlooking in regards to changes to the '89? I tried a search
on this, but only came across the traditional lip-cutting/rolling trick to cure this common cold..
it's getting to the point where i just might get myself some mild fender flare to fit some wider
rims and tires and not have to worry about the low skirts getting in the way... This doesn't seem
like the ideal path for me to travel as I really don't want to worry about the paint as much as
the powertrain maintenance/upgrades at the moment. Both cars ran the same tire, minus about 5/32"
of tread on the tires on the '91. I was looking forward to taking advantage of my goodyear
benefits as an employee and getting a hold of some Eagle F1 GS-D3s, however destroying a nearly
$200 tire isn't one of my intentions!

Any input is greatly appreciated!

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Neno & The Qwik SHO
1989 SHO: SS 3.2L Long block, SS LPM, Ford 80mm MAF, SS CAI, SS UDP's, SS Hi-flow Y-Pipe, SS Cat back, SS Jr Revs Clutch (dead!), Eibachs, Italian Silcers w/ bald 215/60R16 Yoko Avid H4 (Thanks Jack M.)
Coming Soon: IPT Stage 4 Clutch (6 Puck carbonic) & IPT LSD (revised version)

1989 Shaggalic: 18x8 Epic Wulfs w/ 245/40ZR18 Kumho Supra's