i thought the rims on a 2k3 r/t where 16x7 why would you go to 17x6?...
i don't see why you would need spacers.. i have 17x7s on my 2k1 and i've seen people with 18x7.5 w/o spacers.. hell if you wanted to you could fit 20s on a 00+ (i've seen it.. wasn't that great of a look

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*note... now that i think about it.. the tires shouldn't rub unless you've lowered the car.. and if you have you might need to cut the strut stops.