This is my Traxxas E-maxx witch was a 3906 version with the twin 550 brushed motors but has been converted to look like a 3908 brushless model.
heres what i did
Changed the chassis and transmission to the newer setup, then replaced the cvds due to the new size. baught a mm combo and then replaced the 2650kv with a 1500kv. other additional things such as integy skidplates red aluminum T6 turn buckles and servo link.