[b17tuner]

I swapped a 6 bolt engine and just recently a 12k mile automatic transmission.

Everything was swapped in from a donor car, TCU, wiring, trans, tc, axles, everything.

Since I started it up I haven't been able to get the transmission to shift correctly. Shifts into reverse hard (full line pressure) and drive is just 3rd gear all the time. "Limp Mode".
I can't pull codes because the OBDII port is not showing any pulses period.

I've tried:
Checking and making sure the fluid is correct.
Buying another TCU.
Checking for power and grounds at the TCU harness connector.

I know about the two connectors that look the same.
I've tried swapping them to make sure I have it connected right. Would I have to disconnect the battery (clear the codes if there were any) every time I changed the way I have it connected?

I'm lost, I threw in the towel and drove it to a transmission shop but they called me an hour later to tell me they didn't want to deal with it.

Any help will be greatly appreciated.
Thanks,