I installed rack & pinion in my 55 t-bird this past summer.I didn't use any kit but I got my ideas from looking at pictures of the Fatman's kit.
  I went to the wrecking yard and found a center steer rack that was out of an '87 Buick Skylark. This type rack mounts against the firewall on front wheel drive cars and tie rods run from the center of the rack to the steering arms at the top of the Mc Phereson struts. By using this type rack you can build mounts from the bottom of your frame to connect to the original mounting points on this rack. You mount the rack in the same place as the drag link on your T-bird was originally located.
  This keeps your tie rods mounted in the same place as they were originally mounted on the drag link and this will keep your steering geometry same as it was originally, this will prevent bump steer from suspension travel.
  I had a friend weld in the mounts for the rack and he also modified my original steering column. We cut the column to extend just into the engine compartment abt. 4" and he welded a tab to the column where it comes through the firewall and drilled the tab so I could mount the lower part of the column solid to the firewall.
  We cut a bushing out ½" nylon cutting board scrap for the steering shaft bushing. He found the cutting board at a meat packing plant scrap pile. (he's a scrounger, amazing what kind of scrap stainless counter tops & nylon cutting table tops etc. You can find at a place like that)
  I used the collapsible shaft out of a late model Chevy with the factory U-joints at each end, I just cut the shaft to fit my situation. My telescopic steering wheel still works.
  I hooked up a horn button under the dash but when I find time I'm going to try to fab. up a rub plate with more of the nylon board and some copper plate where I can run a starter brush against it and get my horn working like it should thru the horn button.
I went into this project with just an idea and blind luck, if I were to do it over again I would do alot more measuring, look for a rack with more travel (I lost some turning radius with this rack) and try to figure out the horn problem before I got it all buttoned back together.
If you will check the Tech Articles for Rack & Pinion, you can see how Jim Culver mounted the rack in his 56 Fairlane.
Hope this info help you decide what to do, But I can tell you in my case I am very pleased with how my steering turned out, the car handles great, seems to be compatable with my original power steering pump (abt. 1800 miles so far and no leaks, or whining pump) and steering "feel" couldn't be better.
  I didn't rebuild the rack that I got from the wrecking yard, I just looked for a good clean unit that had all the lines and hoses intact, good rubber boots and had all the mounting hardware. It was already out of the car so I just came up with the Buick unit by chance, didn't get it for any other reason except convenience. The rack was $35
  I scrounged the yard for the collapsible connecting shaft and U-joints. I think I gave abt. $10 for this. My Buddy had new hoses made at a tractor shop, I don't know what he had to pay but I think it was around $20-25. This is not counting the labor my buddy and I have in it, but we probably have abt. 4-5 hours in it total.

The first picture shows how the shaft is routed on the outside of the steady rest engine support, The steering u-joints and shaft came out of a late model GM, I'm not sure which one actually, just something I thought would work so I picked it up.

Second picture is a little clearer, if you'll look close to the top U joint you'll notice a rubber sleeve, this is where the 2 shafts connect, the smaller solid double D shaft slides into the hollow larger double D shaft.

In the third picture you can see how the power steering hoses are close to the pump and makes for a nice and clean installation.

In the fourth picture you can see how the mount is welded to the frame. I looked at the mount on Jim's installation, but I think it would be more prone to flexing from the side load than the way my mount is located, I guess that would just be a matter of preference though. (Editors note: The Fatman kit uses 1/4” plate and I have not seen any flex whatsoever.)

Richard’s Mount Above / Fatman Mount on Jim’s Fairlane Below

In the sixth photo you can see how I used the tie rods that came with the rack instead of the tie rods that were on the T-bird, this is the reason the tie rods were a little short on my installation, in Jim's installation it looks like he used an adapter to get the tie rod ends separated to the same distance as it would be on the original drag link (see next three photos).I haven't noticed any bumpsteer with the way I've got mine setup, but to keep it the same as original you would know you are setup right if you went with the adapter. I did have to use shims on the ball joint tapers also because the Buick tie rod ends were smaller than the T-birds.

The last picture on my photo page is pretty blurry but you should be able to see how the lower part of my steering column was cut to extend into the engine compartment abt. 4", you can also see that my buddy cut a plate in a semi circle shape and welded it to the column so we could mount it solid to the firewall. It also shows the nylon bushing that was cut and press fit into the column and how the steering shaft was left abt. 3-4" longer than the housing so the telescopic column could extend and collapse and the shaft would slide in the lower portion of the column.

  As far as how much steering travel you will need? you need to measure how much travel you have now and how much travel the rack has that you are looking at. My turning radius isn't real bad but it is a noticeable difference when trying to turn into a parking space and you need that little extra bit.
  I hope this information will help you decide what you want to do. In my situation my steering was shot, the cost of rebuilding back original was terrible, my car wasn't original and all along I have been building this car to be a good driver that I wouldn't be afraid to drive anywhere. As for now I'm just going to relax and try and enjoy the T-bird next summer, I am hoping to take it on the Power Tour in June and make a few Goodguys shows next summer. Goodluck on your T-bird steering, and feel free to ask any other question you might have about the way I've got my T-bird set up. Here's a link to my home page that explains some of the stuff I've done to it and the parts I've used.http://hometown.aol.com/a%2055%20thunderbird/myhomepage/profile.html

Take care, Richard