I have a 1990 chevy k1500. I would like to install a jets performance chip to add a few extra ponies and to enhance the overall economy of my stock 350 motor. I was told that my truck would would not have a removable chip, but instead I would have to install a PCM (power control module) Questions: 1) is this true:that is-pcm instead of removable chip upgrade, 2)where is it located and 3) is it even worth the trouble? Any info is greatly appreciated.