I have good news (for myself
. The Bonneville is working fine. I took it to an AAMCO shop and they said it was the transmission and it had to be rebuilt or replaced, it was messedup and in the wrong gear, and they did drive it around the block. Because it didn't make sent to me since it worked OK when cold, I went to another transmission shop, kind of a family shop, I didn't take the car because I didn't want to force it anymore. I just described what the car was doing and the guy told me to check the computer. So, I went to a junk yard and got a used one, $75.00, and replaced it. The car is working fine now. I drove it for about 45 minutes and no problem. I don't have much doubt that it is OK, I will see in the next few weeks.
I did put back the old computer and it does have a problem. Now, I think this is important, in my experiments I discovered that if the battery in the car is low, the problem is much severe. When I put a battery that I charged during the night, the car did hesitate etc. but the transmission didn't feel like dragging a heavy load.
Tony