Biggun

I have an old duratrax warhead that I picked up a few years back. I experienced a few problems with it and it got put on the back burner. Well I got to looking at it and it has a pretty good chassis on it. I want to bring it back to life. I want to make a full custom deal out if it but I have no clue where to start or how to. If someone could point me in the right direction it would be greatly appreciated. The only think that I am positive of is that the motor has to go that thing was never very reliable. Any and all help would be appreciated.