Strange wheelbase on K30 4x4 bought today

[Devillusion]

Ok....I've owned ALOT of square body trucks ranging from half ton short boxes, to crew cab long, blazers, suburbans, etc. One thing I have never owned till today was a K30 4x4 regular cab...cab and chassis.

Most will say "okay? and?" well here is the twist I have never ran into. The truck is a regular cab, single rear wheel, 4x4, D60/14, T400/205, 4.10s. All good, great, very happy. Here is where it gets weird....the wheelbase. It is around 4" longer between the cab and axle, and an additional 4" or more off the back of the frame. Truck was a fire rescue with a service body on the back, frame has not been stretched anywhere.

This is going to be my full out trail rig and will more than likely get a crew cab set onto it in the near future and looks like it should work out perfect for me. But still stumped on the length etc.....just curious more than anything.