This is an Epic Ork Trukk which I converted.
It was done for some additional rules for Epic 40000 which appeared in one of the Epic 40000 magazines (remember them). This is an Ork Trukk.
Take one Ork FlakWagon, use the gunners from some Warbuggies and place where you would put the Flak gun.
One thing about this model is that it has had an ink wash and as a result is rather glossy as I did not know at the time to add paint to wash mix which removes much of the gloss.