Thanks guys.
Terry37 - I'm leaning towards Axles & Alloys II (for its simplicity), but Car Wars or any other ruleset would work. They're die cast cars with big guns
Maxim - Yeah, I'm still not sure on the Land Rover. I'll see what it looks like painted. (It's not really a scale issue, it is its proportions that seem a little "off" - a little too wide perhaps.)
The plan is to have everything undercoated before the weekend so I can paint them then.