Thanks for your response. I guess I should have just had my 93 transmission rebuilt. I assume that by opening up you mean it has to be pulled out and basically rebuilt . Not something that can be done from taking the pan off.
So I found a 1994 4l80e transmission for 600.00 that came available because the 6.5l diesel suburban it was in caught fire. The harness and speed sensors were melted but the trans fluid was clean and the owner claimed it had only 18000 km on it. After some time I had a transmission shop install...