Want some big ass tires for Revo hill climbing, reccs?

[Finnster]

I want to get some BIG tires to run for some hill climbing, winter driving, and some light crawling for my Revo. I want to run 40 series. Can you get Moab XLs to fit onto 40 rims? It says they are narrow and require prolines special 23mm beadlocks.

No, I'm sticking to my 17mm hubs. Can you narrow the rim enough? Are they they really unstable for anything but sloooow speeds? I could go to the reg 40 Moabs or such, but they are sooo much heavier, but I would like something not too overly specialized so I'd have to constantly be changing tires. Maybe just 40s mashers to compliment my maxx mashers?