same old stalling issue, but different symptoms
Solenoid pack isn't hard to do at least on the e4od. I think it was about 100.00 from ford, plus the cost of a new trans filter and fluid. When I replaced mine, it was actually a faulty wire harness so you should give that a visual inspection too while you're down there. Also make sure the filter goes in tight as sometimes they come loose and cause issue.
I am not sure what it looks like. I had my trans rebuilt and the solenoid the trans shop put in was bad so they replaced it. Google transmission solenoid block. I think it is a piece of aluminum with a lot of channels machined in it with an electrical connection. The part I saw was $200.00.
Don't know if its applicable here, but on chevy transmissions you can easily put in a shift kit (heavier springs) to make shifts quicker to fix problems with slipping and poor shifting. You might be able to put in a shift kit and help the problem. Just a thought, I bought a shiftkit for my brothers grand prix for like 30 dollars.

