Here was a good article on this but the site appears now to be nonfunctional. Anyone know the author? Here's a crappy scan but it's all I got. It basically said to use '92 V6 4Runner calipers as they are the biggest pistons but you may need to update your mastercylinder to a larger bore to push enough fluid, your wheeel may hit the larger calipers and you have to trim the backing plates.
EDIT: after re-reading the above link it appears to be the same thing. The scan adds a little more info on how and why. I used these and had to grind very, very little to clear my 15X10 MT Classic II wheels.
The next best may be
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