Pedro, the very adjustment of an automatic transmission is not a rocket science if you just follow what you have here and in technical manual. I am not a mechanic, my mechanic did not know these gear boxes, but we did it. Just follow the procedures described.
However: in order to do that, you have to have the idle correct and vacuum correct first (meaning vacuum just needs to be there, undisturbed by e.g. brake booster leaks). That is what I learned here.
You also need to have a gauge for pressure and a banjo connector. We also made a "special tool" for turning the adjustment screw, but it took us 5 minutes when we saw how this screw looks like.
Perhaps more senior colleagues will see somthing else in the sympthoms you described - again, I write only about topics I went through with success - but if indeed it is about adjustment, it is not that difficult. You check the three way solenoid operation, you connect the gauge through banjo to the place from the picture, disconnect the vacuum line, run the engine and compare the pressure reading with the one from the book - you will know. It may be too high in your case. Then you just turn the screw. Just be careful with pressure units conversion from various sources.
