I am looking to buy a C4 tranny for my 91 notchback that I am converting over to a V-8 car. I don't have the first clue what to look for. I have heard they differ from year to year also, so which is best. Keep in mind that I am on a major budget, so picking up the phone and ordering one is out of the question. I prefer to find one used in the trading post or online.