Although I never did it with my old SVO, I was seriously considering it and seems as if it would have been fairly easy. I was planning to go with a flaming river manual rack and steering shaft for the foxbody Mustang application. I would have then used a pair of shorter belts after I removed the pump.
It almost looked as if the power steering pump and alternator bracket were one in the same on my SVO. So I'm guessing I probably would have had to source some accessory bits from non-power steering 2.3l Mustang to do it right...but I don't think this would have been necessary.
Not exactly sure what the process would be for a Tbird. If the Mustang rack won't work in the Tbird, perhaps you can source a factory manual Tbird rack from a company who remanufactures them or find one in a junkyard.
Have you tried turbofords.com? Check out
www.svoca.com too. It is an SVO dedicated site, but you may find some useful info in the forums.
Wish I could offer some more insight. This was something I was looking into for my '86 SVO before I decided to sell the car. Good luck in your project!