Got that 9' inch from Leed on my 73. I like it for creating space in that area for all the additional wiring/relays etc.. of my Sniper.
The feeling on the pedal is less smooth than with the 11 but perfectly fine. They come with 2 rods to accommodate both 71 and 72-73 models.
That was 2 years ago. Since then, I have restored my 71 booster. It was rusty and there was brake liquid leaking from the back of the master cyl into it. I thought it doesn't matter if I try and fail, as sending the core to the usa and back makes it simply too expensive vs buy a new one.
Turns out that it's a pretty easy thing to do, and while I've found some membrane/kit to service it, I have ended up reusing the original membrane because believe it or not, Ford, (Bendix for Ford actually) made the membrane out of the most durable and expensive rubber known to man ( the so called Dupont quality, now days costing 100x more to produce than regular rubber that will start degrade in a decade or less) and after a good clean it was as new and I'm confident it will last another 50 years easy and I ended up not using the new membrane of lesser/modern quality. I did replace the dust shield and rubber washers at the valve.
What usually cause them to fail, is either the rust at the bottom on the engine atmosphere side or at the valve side when the guide made of bakelite breaks or the one way valve that you could actually change without even open the unit.
Here a few picts taken during the "surgery"
Note here that I was told once done, that I could have just free the 3 main tabs and then tap to unscrew both "donuts".
Just like the extra pass they offer at booster dewey, I've also plated the donuts in and out, but a good paint alone would do fine.
The job is mainly to ensure that the contact area of the "donuts" to the membrane is really smooth so it evenly squeeze the rubber once back together. Focussing just on "fixing" it, you're looking at a couple of hours of work. Only thing/tool you really need is a way to keep it pressed together during de- and reassembly.
Knowing what I know now, I could have saved money on the kits as you can buy kits for Bendix boosters of that era that are not the same for the membrane (that you can reuse as original are made of exceptionally superior quality), but they are exactly the same for the rest and cheaper, like the one way valve, grommet and valve dust/rubber spring washer.
