Bedrock,

Word of caution. Don't assume that offset will help judge the ability to clear the brake calipers - it doesn't.

Offset is the distance from the centerline of the wheel (as if you cut it in half, and each half is still a circle) to the mounting surface of the rim (where the wheel touches the hub with the lug nuts. This spec does NOT tell anyone how much further away from the hub is the 'spoke' area of the rim. It is that distance (and its 'width' as well) which is not specified anywhere that determines brake clearance.

If it were possible to determine the brake clearance issue just by looking at the specs, then there would be far less speculation on these forums about which wheels might fit an 05-06 X, and places like Discount would not need to do 'trial' fittings of rims prior to purchase.

FYI, having a rim with 12mm offset just means that it will stick out ~1/2 inch further away from the body of the truck than say a 25mm offset rim - again, not necessarily any more (or any less) room for caliper clearance.