[Bob Kontak]

Throw it up on some jack stands and get under there.

As soon as I give you a thought, you know, it will be the other thing so I am just thinking out loud here.

I suspect if oil gets in the exchanger it will be hot enough to smoke. Thinking you have pooling either on top of or in some "remote" place in the exchanger. When you do the hard right hand turn the pooled oil flattens out to the left getting closer to the exhaust pipes.

Doubt the cylinders are leaking. More of a 964 thing. Not so much with the 930 case.

Oil return tubes could drip down on top?

If you do have to remove your exhaust get Maap gas instead of propane and heat the nuts up as red as you can get them. Bruce Anderson says cherry red but don't know if maap gas can do that. A nice orange at least. :-)