trying to install factory stereo that i bought used, dont have the funds to get an aftermarket just yet. went to the junkyard and got the old twin harness off another camry (connectors are blue) however wire colors seem to match accordong to installdr. com question i too found that enclosed transformer thing-a-majig and according to this previous post it goes with the old stereo unit, how? and i'm in the process of connecting existing wires coming from car to new harness i got from junkyard. do i need that transformer thing and how/where does it go? any tips would be greatly appreciated.thanks in advance guys.