I'm Now wanting to get this

http://cgi.ebay.com/ws/eBayISAPI.dll...m=130181401990

But I want to know if you can exchange the shells out, as in same everything except the kind of shell? because he has Multiple ones on there and says that all i have to choose is the shell and it will be the same 1/8 truck... Sounds Wierd to me but I'm new to this so, Please someone help me before i buy... thanks