Durahl and jha13 thanks for chiming in. I did move the battery to the front of the hull, after seeing a post on this forum (I think it's by Fsttanks ) and added some extra weight (including a bag of hardware and an old steel watch) also to the front mainly to make the tank more balanced. They do make a HUGE difference for crawling uphill. But the hull is very roomy and I could definitely add more weight. The tank is slow enough and it shouldn't add too much stress to the gearbox.

Making it crawl on my rock garden is 3x more fun than a RC crawler. Perhaps it's proportional to the number of roadwheels

I've recently made a YouTube video of it but I've posted too few to be allowed to show it here. If you search "RC centurion tank super realistic EzRC" you should be able to find it.

Cheers!