My Bad, I was comparing my 900GMT 2500 to my cousin 800GMT 1500HD.

So they are not apples to apples.

Probably the same GMT are same frames, or same truck. Don't know.

To the op, I got my rims from eagle wheels. +25mm offset and they stick out at least 2"

here is a link for the options http://aewheel.com/wheels_detail_specs.cfm?id=448