I think dad may have already put a new master in, I'll have to go under the hood and look. I checked the website, and Turner recommends replacing the master at the same time you do the disc brake conversion. Relying on that emergency brake cable to grind to a halt is a slim reed!
It's definitely not concours and I'm not into that (my late father in law was, but he was a pre-1939 man and that is WAY out of my league!) and dad has made all sorts of odd modifications to the car along the way. Some - the aerobatic harness and the caution placard on the glove box "CAUTION - Do Not Open Windows At Speeds in Excess of 120 MPH" - I kinda like, others (the black plastic replacement rear view mirrors) I definitely do NOT. I think I'm going to try to take it back to original cosmetically (except for the placard!), but with the running gear, as far as I'm concerned, anything goes. (I'm not doing a thing to the engine, though, I've never heard one purr like this one. My only complaint is that the radiator is too small, and there's NO ROOM - you couldn't fit a dime in the engine compartment.)
What was the T-5 tranny originally built for? I had OD on my TR-6 and (other than the fact that nothing that Lucas had a hand in really works right) it was nice.
If a manual transmission and clutch sound like a painful modification, another popular transmission swap choice is the GM Turbo-Hydramatic 700-R4, a 4-speed automatic with overdrive.
It seems that both swaps entail some degree of difficulty, but both seem to really enhance the experience of driving these older cars. A friend of mine put a T-5 in a '66 Mustang and welded up a shift handle that looks just like the old factory 3-speed shifter. When you grab that knob to row through the gears, though, the shift lever moves through that tight, short shift pattern. I think I need to do the same to my '65! :-) If you consider the T-5, be sure to avoid the ones used in Thunderbird TurboCoupes and similar Fords with the 2.3 liter turbocharged 4-cylinder. The gear ratios are wrong for that 289, and the torque ratings are way too low. The T-5 install actually sounds easier; the 700-R4 is a big beast of a transmission that may require modification to the floorpans. Wish I knew more about the Stude 289 engine; the last time I saw one was about 25 years ago when a neighbor was working on his Studebaker pickup.
Check here for some transmission swap details and links.