XT8 questions.

[nativepaul]

I'm turning my buggy from its on/offroad rally setup to a full onroad setup and with that I wanted another vehicle for pure offroad, I have a used Xray XT8 coming for xmas not sure how old or if it matters, I ordered Mikes motor mount and battery tray for it but after reading through a lot of XT8 threads I cant see a reference to the spur gear, do any plastic spur gears fit the XT8 centre diffs? if not are there other diffs that do accept plastic spurs that fit in the XT8 dif mount? After a lot of running I have had no trouble with the kyosho plastic spur on my hot bodies diff in my buggy and would like to carry on that tradition with the Xray rather than start eating hardened pinions with a steel spur.

Also as this one will never see the road but will see some rather soft mud and big jumps I would like to make it a bit more "monster" with some big wheels and tyres to avoid it sinking or bottoming out what are the biggest wheels/tyres that fit? Can I go even bigger than that easily by changing hexes (if so how big and what do I need to do it) or will that limit suspension/steering travel?