you cannot properly install a system without a good remote turn on. if he doesn't want the factory radio removed for a half hour he doesn't want a sound system.

only bypass to this is ghetto (especially for a almost new car) - a switch at the dash. turn the switch on last and off first every time. you can give it power from ignition instead of battery so they will always be off when the car is off. if the amps are left on (even with no music) they will drain the battery.

take the car to a professional installer if your "client" doesn't have enough confidence in you to pull a factory radio. i can't see how he would prefer you jerry-rig the stereo.

i deffinately understand you guys, dont get me wrong. but i cant just tell him no. he doesnt have the money for it. and his dad wants it to be able to be uninstalled when he goes away for college. and i will make sure that i put something over the wire or ill run it where it will be protected.