You can order the P-chassis as a complete assembly minus body from GM. Find a Chevy or GMC dealer that does commercial orders. You can specify the length of the wheelbase, chassis, engine/transmission, axle and ratio, and GVW of the unit you order. It's not as much $$$ as a complete, ready-to-drive truck, but it can be driven, since there is a seat and all of the controls present. It's designed specifically for customers that want a custom body put on their chassis. The Grumman aluminum-bodied vans are a perfect example, as are the UPS trucks.

I've always wanted to do this, if I could find a nearly-perfect COE Chevy/GMC or Dodge cab to build as a hauler.

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