Probably too late, and...
...I don't mean to confuse the issue, but I may have been one of the contributors to the original confusion.
I did a J-mod/Transgo shift kit install on my '95 4.6 a couple weeks ago.
Because that is both confusing and somewhat contradictory to the previous advice, let me explain.
I have zilch experience with cars newer than 1982 --what I call "computer cars."
However, I knew that the MN-12 had tranny problems before I bought the car.
I also precious little experience with automatic transmissions, and didn't want to double it on a car that I'm still making payments on.
So, I researched and I dug, and I worked on other cars, until I felt good enough to do this one.
I bought all the J-mod parts, and a Transgo shift kit (with movie).
After thinking about this for some time, and noting the "flavor" of both modification processes, I did all the J-mod stuff to the tranny, and all the Transgo stuff to the valvebody.
With two exceptions. The J-mod centers mostly around springs, servos, and pistons, the Transgo centers more on valvebody bits and pieces. (The movie even shows them sticking the "bad" accumulator pistons back in there...)
I added one of the springs from the shift kit to the J-mod list, and I drilled one separator plate hole "in-between" the J-mod and Transgo specs.
And, I'm happy. For the most part. Yeah, I gotta be careful in the rain. Yeah, I probably built it "stronger" than I needed to, because the 1-2 shift is really taking some getting used to. And, it won't do a burnout, unless it's in first, and even then, it ain't the the stuff mosquito foggers are made of.
Then again, I'll be adding the 3.73's as soon as I get the car and the tranny paid off (soon?) and the blower when I win the lottery (or sell some internal organs).
So maybe it'll get better.
A-Joe, I'm happy enough -- at least it doesn't run any worse than it did before, and I feel that it'll take a couple trips at the track without killing it.
Personally, I did what I had to do to feel good about the job. Next time (lol, never!), I might just stick with the straight J-mod.
However, if you're a cheap bastard like me, and you've just GOTTA use up as many parts as you can, feel free to e-mail me for details. I'm in the process of committing them to computer file so that I can remember all of it five years from now, when it blows up.
Dreaming of gears and blowers,