Cams probably won't give you a big gain and they're not the easiest to install (nor are they super cheap). I know it's more than you want to spend, but save up and get a good short shifter...B&Ms is around $100 I think. I wouldn't trust an ebay shifter not to break at the worst time, and if you can't get your car in gear, you can't drive it. A Kartboy SS was my first mod and by far one of the best for this car...I don't know if I could ever go back, the shifts are so short and precise. As for your strut question, when they fail they'll start leaking oil, ride quality will be awful, and your handling characteristics will change (not for the better!). Good luck with the header install...make sure you thread the egr before you bolt the header to the engine!