the boosters i had,both from 55birds where the same as cars except the mount bracket. simple how they work,they boost the had pressure with vacuum. the had portion has a brake cup that has a hole so if vacuum to booster is interrupted you still have some breaks
i rebuilt 1 for my 32ford and had problems getting parts,midland dealer hear claimed no longer avail. purchased som on treble bay. thewhol issue was a wast for very little  boost. sold the core and went to  proper booster.

They work, given the times. So did the treadle-vac. You won’t confuse them with modern brake boosters, or the light effort I remember from Chysler products in the early 60’s. I’d say if you’re comfortable driving the car leave well enough alone. If it’s marginal (like some of us old guys with bad knees and shoulders) power brakes and steering are more attractive than they used to be.

If you want to get a brake booster rebuilt I have a suggestion. Power Brake Exchange, San Jose CA.
Some years ago I need a booster on a 1963 Jaguar MK2 sedan rebuilt. I called and they said they could do it. I took it in
and I asked when the last time he had seen a booster like that he said they had re-built  4 or 5 of them that week. 
Excellent work but NOT CHEAP. Pete

If you don’t find the brake effort excessive, a booster isn’t going to be a big improvement in my opinion. If you’re on anywhere near stock tires and the existing brakes are good you can probably already lock the brakes. The tires are the limiting stopping factor. Modulation at lock up is kind of tough with drums, and a booster probably won’t improve that.

I had one of those power units at one point, but it was a part of a kit with a dual master, power front disc, and manual rear drums. One of the major thunderbird suppliers. It worked fine, it’s been replaced for other reasons.

I don’t find them an attractive option, either appearance wise under the hood, or for braking effort. My first 55 bird in ‘67 didn’t have power brakes and I wouldn’t have added them. But that’s just me, and what I value. I’d be replacing chrome, doing the interior, putting in an original radio converted to modern components, lot of things first. But that’s just me. It won’t hurt the car or do much if anything to change the value.

There were several times I didn’t think age was going to be a concern for me, either. Most involved cars, boats, or skiing down hill off the trails. But somehow I got lucky and I got old.

Each and every guy on here has his own opinion of what he thinks is important to him and his car. My cars paint is fine the chrome has all been redone and the interior is brand new, .and I upgraded the radio last year  I have been working on this car for about 10 years , it has taken me so long because  my family has always come first . Yes I think the brake booster is more of a novelty than a necessity but as a recently retired NYC police officer I find myself with some spare change. I think buy the time I am done I will have about 500 into the working power booster unit, and I picked up a power steering set up for 400 . So i do not think I will be  over  doing it if I  dress up a Glass top 1955 Crown Victoria. I want to thank everyone for the leads to rebuild the unit but for the most part I will be doing that myself.  .I am presently working with my neighbor restoring a 1956 Club Sedan I hope this does not take ten years because I may not be able to finish it with him . Thanks for the replies  this appears to have been a very active thread.

I have an OEM bracket so the booster attaches perfectly. I've loaded up Daniel Jessup's CD set of manuals on my laptop and I've been using it to inventory the parts I need. The only hose I'm having trouble matching up hose 2078 that goes from the booster to the distribution block on the frame. The other items I haven't found are 354316, 17597 and 87943. The wrecking yard near me doesn't have any 56 Fords.
I'll have to check if my printed manuals have any hardware descriptions, I have a feeling they might.

Hello did any of the boosters come from ford all black or were they original finish with the aluminum polished and what appears to be anodized chambers. Most of what I have seen are all black , I assume they are rebuilt. 

https://www.npdlink.com/product/block-manifold-vacuum-connection/167469/220640

This fitting(s) is for BIRD.

FORD is 354316-S

EDIT -

Notice NPD shows two different fittings under the same PN. One is 1956 and the other 1957. You have to know what you are looking for exactly as the vendor may have no idea or incorrect listing(s).

Basic PN 17597 is a vacuum source for the wiper motor without a two stage fuel pump. The fitting is also described under BASIC 17597.

All of this depends on the year (55-56-57) and what accessories were assembled on the vehicle (whether FORD or BIRD). Most info was deleted from cataloging. You would need period cataloging and most likely an ENGINE ASSEMBLY MANUAL to figure out each assembly detail.