I'm finally done with the basic version of my ork Battlewagon with integrated death rolla. Only spare parts from different gw kits were used. The big shootaz on the small turret can be removed and replaced by 2 bazookaz (magnets).
But there are still a lot parts to be painted including the cover for the cargo area, including a leman russ turret with a big cannon. Another small turret with only 1 big shoota and ork boy, with attachable grabbing claw.