RE: 8ight-t chassis change
If you use your 427 with the drill start on the race roller chassis you will have to use the rtr engine mounts to allow room for the drill start back plate. The race roller chassis is a little different as it is not recessed out as much as the rtr chassis is where the drill start sits at the back of the motor,because it is meant for bump start engines. So when you mount your 427 with the rtr mounts the motor will sit a little high in the back. I mounted my friends 427 on a new chassis like you want to do and just shimmed up the front of the engine under the mounts. No big deal and it works fine.