New maxx chassis

[maxxdude1234]

Providing you have access to a CNC milling machine and are pretty decent with CAD software, you could do a good job. Providing you use decent quality material and you use some good chassis braces, it should be strong enough.

or

http://homepage.ntlworld.com/ryan.coombes/emaxx.htm

Do what he's done....the easier option.