ORIGINAL: 46u
When I sent back my chassis they sent me a new motor plate as from what I understand the old one will not work with the new chassis. The new motor plate is cast. There has been several chassis up grades for the original Nitro Rush. What you get now is a black Evo chassis. I actually have the first up dated and the last up dated black Evo chassis. The first up graded was still purple but thicker with the same sorry flat motor plate.
Actually, it'll work with the old chassis, there's just one little stump you have to dremel off if you're still using the stock upper deck.