1BOSS83

83 Hurst/Olds, car has headers on it currently. It is time to replace them as the drivers side has a serious leak due to a crack in the collector. Moreover I need to put in a new dip stick tube/starter so this is going to be a multi bird via 1 stone deal. I was pricing and most are in the 200-250 range. Any recommendations on brands? Primary size? I assume I have to drop these from the bottom. My main concerns is I put on new headers and they don't reach or match up with the rest of the exhaust system currently on the car. Considering it has an H-pipe and full welded system I'm trying to be as thoughtful as possible.
Thanks,
-Adam, PA