I have one in mine, just takes the laydown gear box housings and motor plate and a few new holes in the chassis. I used my rb6.6 chassis as a template. Also i had to file my suspension block since i didn't feel like buying the new version. Only thing is that with the laydown, the side gaurds are a bit in the way when it comes to pinion and spur changes. Speaking of, I cut my side gaurds to fit a shorty sideways, i didnt mill the chassis, as i needed to add weight under the battery anyway.