exhaust troubles on 66 barracuda

How about a picture of your adapter? It can be rotated however much you need to; it's not indexed to a certain spot. If there is indeed no room to run a pipe past it, then it has to be angled wrong. Or else your muffler guy don't know s----.

Here's my 67 Barracuda. Best picture of the adapter I have sitting round. There's no one exact right spot, but it should look generally like this.

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