Thanks for posting the pics of the 914 Crown turbo system. It's great to see what the original components of the kit looked like. I recently purchased a 73 914 2.0 w/ turbo. It originally had the Crown kit installed. Over the years it "evolved" as the PO added exhaust manifolds (custom fabbed/no heat), waste gate, intercooler, water injection, ignition boost retard module, permatune, EGT pickup, cockpit adjustable boost, etc.
I received the Crown "installation manual" with mine as well. I've been researching the Crown kit to see what turbo was used in the kit. Best guess is it's a (modified) Rayjay. Clarks Corvair
http://www.corvair.com appears to have components for this Rayjay including a pre-assembled turbine module. If you have located another source for rebuild, parts. info, etc. I'd really like to share/compare notes. If it wasn't too much trouble, I'd also like some close up pics of some of the kit components.