The only mods to the chassis to do this were, I made some stand offs out of some old Traxxas body posts, they are bolted down in the existing battery locator holes, the front and rear tbar ball cups have been cut down slightly, just two of the screws and plastic on each one, and I had to raise the shock mount and ball stud with two washers to clear the battery at full forward with the shock second hole up. the clearance over the front edge of the battery is a little tight under the body, especially with a Reedy pack, Iwll modify my connectors some more to fix that. The ESC in the pics is a Mamba Max Pro, decased and with the heat sink cut down....