This video is on how to install a Revo forward only (or FOC) for your radio controlled vehicle. For this, you will need to remove your 2.5 or 3.3 Revo transmission from the kit and then I will walk you through the rest. You will basically be removing the front gears and then replacing another gear towards the back. Also, I am using the center differential kit which is easier as you do not have to worry about the gearing on the center differential shaft. If you do not purchase the center differential kit, then the extra shaft and gear will go there. The benefits to this installation is to have less rotational mass and weight which will add a little bit more speed to the kit. If you plan on using a big block engine then it will destroy the reverse gears and you will want to convert anyways.