Since the tr4 frame is just a modified tr3 frame,if you were crazy enough , you could retro it pretty easily.The out-riggers are wider but easy to shorten,the frame has bolsters on the sides of the rails in front of the suspension.Plasma tourch time...There are several other minor things but they can be left alone, since they dont bother much.
I guess its better to not ask why this is a question...
MD(mad dog)