She won't fire up. Please help me! I"m at a complete loss!

[jorgensensc]

I'm really at a loss guys. I could sure use your help.I got the l92 /6l80e installed in the burb a couple of weeks ago. I was very careful wiring everything up so that I would be able to fire the bad boy up the first try. Guess what, no go. The engine cranks nice and strong. The fuel pump primes, then runs while cranking. everything seemed ready for the tune. The tuner came over last night and couldn't get HPtuners to see the ECM. There were no High Bus signals. There was power and the grounds, but nothing else. So after jacking with it awhile he left. I stayed up till 1 am and figured out that the computer is sending the can bus signals to the transmission first, then the transmission sends the signal out to the Data Link Connector. The signal is not making it past the tranny for some reason. the signal gets to the tranny, I verified that. And the wires from the tranny to the DLC are good, I verified that. The tranny just won't pass the signal on. There is power everywhere on the tranny connector that there should be. So I read somewhere that if you get the ECM bench tuned, it will wake the tranny up and fix the problem. So I went and had it tuned by the guy that came to my house last night. Got it back home, hooked up, and no joy. cranks, but won't start.

So here I am, confused, and really frustrated. If the internal tranny TCM is malfunctioning, or not waking up in the correct order, would it cause the engine to not start?
Where else can I look?
I don't have a scanner. Should I get one? Will it really help? A couple of tuner guys said it probably won't help.
I'm looking for any solutions or ideas guys. This is my daily driver, and I need to get it up ASAP. I've been driving the '56 Bel Air for the last 2 weeks and it just broke the exhaust manifold yesterday. So now we are down to just one vehicle that runs.
Thank you guys for all of your help.
Shawn