Well my Stampedee has been modified too..
. I this one years ago when the first came out and decided it was two short wheel base so used a piece of .060" Aluminum and made a new Front plate for it. Basically lengthen it 2 inches. I have had two .15 and a 2.5x Pro. in it and jsut decided had enough with the nitros. I have not converted yet but its possible..
I have changed the springs in this one and you can turn is hard to left or right, and it does not flip anymore. It alot of fun to play with. I was thinking of putting a short course truck body on it and race with the short course guys. With all the suspension travel it would be fun..