WWW.Rcproductdesigns.com
I got one for my hyper and was very pleased. First conversion kit on the market for this car, and its well put together, its designed specifically for the Ofna car.
Now, at the time I was experimenting with a 10th scale system. I've since sold it to a buddy who is running an 8th scale system on 4s ( I opted for a single tray) and it screams.
http://www.rctech.net/forum/9156841-post19881.html
Dan is a great dude and his conversion kits speak for themselves.
If you set up your car, it can still be competitive.
Momo