A year ago I built some warbuggies out of a defunct Russian toy called Robogear. Here is that post I built 4 of them but only painted one. Now I finished the 2nd one and added the option of it carrying a Grot Rokkit into battle instead of the twinlinked rokkits.
Here are some pictures:
I magnetized the rokkit so I can easily swap it out for the rokkits (they really shoot, not pictured, see original post). And yes, the launcher swivels.
The paintjob was straightforward with a few details and lots of washes.
Try to find some of this Robogear stuff, it is easily converted and looks great on the battlefield.
Hope this inspires!