QUOTE
Boge strut = boge insert, or Koni-insert-made-for-boge-strut
Koni strut = koni insert only
Bilstien strut = Bilstien insert only
but add "Bilstein" to the Boge list at the top.
Regarding "What you need for a 911 suspension conversion", it will vary:
1. You could get 911 struts. Depending on the year 911 strut vs 914 A-Arm you may have ball joint issues. If you keep the 914 A-Arms then you use 914 torsion bars. The struts are as listed above: Boge, Koni or Bilstein. If you want to get elaborate and raise your spindles get the Bilsteins they have a straight tube however, it can be done on others... just not as easily. My Koni's are all raised. (911 RS and 914-6/GT project)
2. You could get a complete package: 911 struts, 911 A-Arms. This would basically ensure you have the right ball joints and you'd get a slight upgrade in t-bars (from 17.? to 18.?) Bolts right on.
3. Sway bar mounts. Do you have them? Would the 911 suspension you get have them? 911 Suspensions post 74 would be under body mounts. The geometry on those is not as desirable as the through body mounts.
4. Misc. Hardware - Make sure you get Calipers and hubs as well. A complete 70-73 911 front suspension would be my choice for a "bolt-on" application.
If you find Koni or Bilstein struts in the package you're now talking about some different calipers. With the model years I listed those would only be S-Calipers and they don't come cheap. If you could find a system with the Koni or Bilstein struts w/o the calipers you could probably do well with an A-Caliper from a later model SC (steel, fairly common and inexpensive in comparison). Consider further... if you do this you should either
1. ditch your proportioning valve in favor of a "T" fitting or an adjustable one. or
2. consider an entirely different brake solution for the rear. If you're going 5-lug you can try the following options:
914-4 caliper with softer pads and a "T" fitting instead of the proportioning valve. Grind the caliper slightly to fit standard non-vented 914-6 rotors (grind the caliper once or grind the rotors down every time you need a pair)
914-6 caliper. Expensive option #1. Matches the 911 rear M-Caliper but costs a bundle "if" you can find a pair.
911 rear M-Caliper - Exact match to new larger brakes up front. Bolts on and uses vented rotors, needs 5mm spacers either on the caliper mounting ears or behind the brake rotor. NO HANDBRAKE. Handbrake options: in-line handbrake valve which is rumoured to be unreliable when hot braking systems cool and your car rolls in the ditch or 911 handbrakes which is the logical choice that the factory used on some rally and hillclimb 914-6/GT's but requires some fabrication skills
Hope that helps! (God... am I bored this AM or what???)