>>7885803I used a repainted hisstank for my acid rain guys
For your omangan guys, I suggest the star wars tvc imperial tank (the orange parts go well with the flame trooper orange). They can fit in the back and in the open hatch but the driver seat is way too tight.
My wishlist of affordable vehicles for acid rain is:
1. World peacekeepers amb combat vehicle
2. Gi joe warthog
3. Gi joe battle bunker