I've found out that the oil hard line union on the cyl. 1-3 side of the case for a '70 2.0L -6 is a smaller size than the same fitting on the side of a larger -6 (2.7 up).

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The number for the union on the 2.0L -6 is 900.136.013.02 while the same "Connection Piece" (Porsche's description) for the 1974 2.7L up is 999.136.008.09. Rather than looking for an adapter, I guess I'm going to pull the one off the 2.0L and see if it fits the opening in the case of the 2.7S.

Are there other solutions that have been validated?

They only make 1 hard line but the fittings do differ. I have a bunch of the smaller fittings if you need one and they won't hurt the engine Becuase of oil bypass mod.

Thanks for the offer Ben but never mind....worked like a charm! Guess I should have tried it before I posted I just wasn't expecting it to work. That they would have gone to a larger fitting for a reason.....oh well.

There's a choke down on both ends, case and the tank, a larger line isn't going to increase the flow one bit.
The stock line is almost dead on -10 size.

Patrick Motorsports sells the bigger one....