Why is my transmission constantly going out?

What is your question?

I have a 79 international scout that I did an LS swap in. The engine is a 5.3 out of a 2008 Tahoe. The trans is a 4L60 out of a 2007 Tahoe (supposedly). The transfer case is a NP241c. Today is febuary 7. Since Christmas the tranny has failed 4 times. The tranny shop said the trans oil pump is being destroyed each time. They have tried shimming the torque converter, changing out the bell housing and some other stuff. I just had the scout dyno tuned today. The Scout is running good for now but, on the way home code P0741 came up. I did some research and it says that it could be the torque converter locking up, bad valve control body or a bad lock up sensor. Can anyone please help me with this? I did this swap so I can have a more reliable vehicle. I cant even enjoy my Scout because I'm afraid of it breaking down on me. I live in el mirage, az. If you can recommend a good shop that can fix the issue, that would be a great help also.