1 - Have a look at the "skeleton" picture and you may be able to pick out the major drivetrain mod: he added a second transmission, inline (from a Chevrolet). 7 or 8 speeds... 2 gear shifts. It may be installed backwards. Have to clarify that.
The Model T manual at http://www.oldcarmanual.com/ is an interesting read. The T itself was 2 speed, with no gear levers. The transmission was all planetary like an automatic, except the pedals directly operated the bands. There was a reverse pedal, brake pedal, and a shift/clutch pedal. You pressed half way for neutral, in for 1st, out for 2nd. The brakes were in the transmission only. There was also a brake/clutch parking lever, and on the steering wheel were throttle and timing advance.
I looked up the manual because I never quite got my grandfather's story about his father's model T. He had the habit of smashing the reverse pedal instead of the brakes, which annoyed my grandfather because he had to fix the thing. He also had a story about how starting it with the advance set wrong nearly broke his arm. I did get his story about the first time my great-grandfather drove the car: when he went to stop he gripped the wheel really hard and said 'whoa!'.