I would check out the Junfac chassis for the CR01, it has gotten excellent reviews.
http://www.junfac.com/shop/index.php...roducts_id=244
The CR01 is a nice platform and I am considering getting one. Or I may go like JRH suggested and get the new losi tranny with the venom lockable axles and a ladder chassis and build my own concoction.
I look forward to seeing the Navigator crawler. It will be nice to see something different for a change. Too many yota's, jeeps, and clod bodies.