I have a 2003 silverado 1500HD with the quadrasteer. I am looking for options when, not if this rearend goes out. the axle width is approx 71.5 inches wm to wm that is where the wheel mounts against to the same on the other side. From what I have researched the 2003 express or savana vans have a 71 inch width with disk breaks and is a straight axle with the same heavy duty and floating axle characteristics. This will be my go to. I havent measured shock mounts or leaf spring mounts but the rear ends at a salvage yard are less than $300 some of which are lockers. Just my 2 cents.