i cut the intake myself, wasn't bad at all, just shove some towls down in the manifold and go at it. i used a dremel, but used a drill bit type thingy to cut it, don't remember the name exactly, and just used the accufab gasket to outline the area that needed to be cut. now to the gains, i actually installed mine about 3 days before i got it dynoed, didn't really see anything more than 5rwhp, but that was with stock air box, even the silencer. with your car i could see a bigger gain, but i think a cold air would be better first, or very soon afterwards. you do feel a big improvement in the throttle response, i loved it, a little tap and the rpm's fly. bottom line is you'll probably see a bigger gain than me, but still not a huge increase, try the WMS cold air with 95 mm MAF first, then do the TB.