I agree with Oliver.
Look at part #18 in a real Porsche 911 shroud:
http://www.pelicanparts.com/914/Part..._metal_big.htm
This is not part of any VW 911 shroud that I am aware of. The way I see it cylinder #1 and #3 get all the cooling and rob #4 and #2.
Plus the remote oil cooler can be a good and bad thing depending on how you plan the work. You need a big big cooler with air flow to keep her cool, like in the Porsche 911 C2 and 993. No little 3 pass tube crap cooler will do the trick.
But what is sweet it that you can run a true 911 cooling system with t-stats so the cooler so the oil will heat up quickly.
As for the Golf alt... I have no idea of its lifespan.
Also I agree with Alex. There is no way I would cut an early "W" lid just for a shroud. But the modern Beetles I could
