This Orkish beauty is an orkified Hanomag and makes a very nice proxy for an Ork War Trukk.
The 3d file came from somewhere on the interwebs and was very reasonably priced. I scaled it to 15mm, then I added the turret from another 3d file by simply printing that out separately and affixing it to the main body of the vehicle via way of a metal washer. The washer was super glued in place and the turret "affixed" by way of a certain grumpy looking 15mm Ork whose base was larger than the washer's hole. With the ork fixed to the turret, its base acts as a stopper preventing the turret coming free because of the washer. A nice little trick that permits the turret to swivel whilst having the ork poke his head out from the top of the turret. Meanwhile the orks base locks the whole thing in place with good freedom of movement.