hey if i were to do another iqr mod i would put a 600 HO with a 660 kit.Easy fit for a pipe.Good power to weight ratio.
Find a rear rmk skid.(iq or rmk, if its a rmk u will have to mod the width a little)
Longer track-depends on rear skid set up. (144 Min)
Tunnel extension and a oil res.
U can run your spindles but they are heavy, 900 a arms bolt right up.
BIG FUEL TANK!
Dont be fooled about making any money doing the mtn mod.....It costs WAY more than u think it will....but its worth every penny!