You also need to address the converter lock-up which was computer controlled.
In previous threads, I was advised that all you have to do is run a switched 12v to the upper left plug on the terminal located on the left side of the 200R4. I just did that on my '72 and ran the 12v through at on-off toggle switch on the console. I'm going to run with 3.08 gears. Can't tell you the results because the car isn't on the road yet.
On my '86, I used a TCI kit. I also put the toggle switch in the power line. It helps if the trans starts "hunting" as mentioned above. I'm running a 3.42 gear and a warmed over 406. Mileage still sucks.