Speak of the devil... here I come
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From reading this I take it my '70 914/6 is mostly the same as similar vintage 911 setups save for the different style parking brake?
Well, in saying that you tend to marry front and rear suspensions and then the answer is no. The rear suspension, because of our mid-engine configuration, is totally different from a 911. It is all 914 with the exception of calipers, rotors, hubs and stub axles (CV's and axles too) When you get down to basics, yes... 48mm pistons, same calipers up front and both share 38mm pistons in the rear albeit on totally different calipers.
You're about 99% accurate on the front end. The only difference I can see between a 1970 911T front end and a 1970 914-6 front end is the torsion bars. The 914-6 has special torsion bars that have the spline count of a 911 yet the spring rate of a 914.
NOW... why they simply didn't use 914 A-arms is beside me. It could very well be these suspension modules came "complete" and for economies of scale, they would be interchangable with the 911 bits. I have a factory video from that period which shows them installing a front suspension complete (brakes, struts etc.) on a 911. So, I would guess they simply used a completed 911 front suspension spec'd with 914-6 17mm weighted bars.
John is right... simply take these bolts out yank/replace and install those bolts. No conversion could be more straight forward. However, there are a few "varieties" to choose from.
I like to keep 914 a-arms for street and narrow bodied cars. This means you can probably get by with a simple strut purchase and swap. If you're going road racing I like the 911 arms as they afford a larger variety of t-bars.
I like 911T Boge struts (914-6 struts) for street and/or narrow cars and either vintage Koni/Bilstein struts with the 3.5" ears or later Boge with the 3.5" ears for wide body/racing cars. Also, get the a-arms for wide/racing cars as explained above. The 3.5" spacing allows the use of many upgraded calipers (S, A, Carrera etc.)
There probably should be a well defined list available for those interested in this fairly common process. I agree.
Basically: Emulate a 914-6 if you want a nice set-up for a narrow bodied street car and, emulate a 914-6/GT for more advanced use and performance.