I have a decent list of mods I want to get installed on my car. A new clutch, fly wheel, header, and a GM stage 2 supercharger kit with a 2.8in intense pulley. I know I have to get the PCM flash done at the dealership...would it be cheaper to have it done somewhere else...or would it be best to get it all installed at the dealership. How much would it cost to get everything installed at once?