Ok, seems a couple of things are still somewhat unclear:
1)Yes, 911 suspension parts are widely used among 914 people. BMW 320 calipers are also used very often to increase swept area.
2)No, any engine that's not stock is not a "bolt in". But there are VERY good kits for the Chev V8 as well as older 911 engines. Any flat 6 over 3.0 liters is not recommended and will require serious work. The 2.7 and 3.0 make good transplants though. The tranny will take ~230 hp stock so long as you don't abuse it (the 901 sideshift that is).
3)Avoid water-cooled engines at all cost. They require significant modifcations to hook up a cooling system. The only reason I recommend the V8 (renegadehybrids.com) is because their kit is widely known as excellent. Don't go for the EJ25. I hear the VW 1.8T hooks up well, though I can't confirm.
I just can't wait till I can find a decent 914 on my own during my co-op work term. I need money. And a decent selection of 914s.