wheel spacer ?

[13lazer]

i just got a nice set of 6 lug rims from a lexus suv. they look good on my c5 blazer. i need to add about 1-1/2" spacer to get them to fit. i know i should eat my vegetables, wear my seatbelt, and not use wheel spacers to compensate for backspacing. im running 6 lug drums in the rear 6 lug discs in the front. my main problem is that the rear wheels barely clear the joint at the wheelhouse/bed floor. are some spacers better than others? what are some of the differences? im gonna check ebay, i appreciate any advice before i bid.