The only GOOD sites I know of for reliable info are
http://forums.aircooledtechnology.com/
http://www.912registry.org/
The first one is dedicated to building a VW type 4 engine, which is used in the Porsche 914's, 1976 Porsche 912E, VW 411/412, and 72 and later VW Type 2 buses. You'll find boatloads of valuable, usable info there with enthusiasts who give a damn what you're doing with your car. All of the newest techology for these great cars reside there.
The second one is just that, THE site for the Porsche 912.
Become a member of both and you wont be sorry.
Damn, shoulda looked at the post date