was considering this,then,wtf,front of cab is sprayed in silver.huh.

It says "Very collectible as it is a prototype which has a galvanised cabinet."
Don't know how that makes it collectible, but both the front and the back of the cab have steel plates that wrap around the sides.
Hard to see from the photos but it looks like the side rails step up over the plates.
Maybe a previous fix up or reinforcement????