Get a roller chassis on Ebay, the Losi conversion kit is keyed to some of the milled parts of the chassis.
I run 4S, 5000mah Zippy packs and the MMM, 2200 on my 8T is a beast, faster then nitro easily it can reach 60mph onroad and geared for dirt tracks can really tear up jumps. Runtime is an issue, if you need to do 20min mains. 4S is good for at least 15min pushing 20min would be hard to do. 5S 5000 would probably be a better match for the Truggy. I got my packs to work in both my buggy and truggy so I made the compromise.