Talk to Pi on SM... he's dumped the ECU for both GE and GTE and will probably be looking for something else once he finishes reverse engineering it.... actually there are a few engineers working on it over there... crazy stuff. I never dug very far into the unit (SuperMonitor), planned on it and bought extras too, but they (like so many projects) grow stale with anticipation in a box in a storage unit. Anyway, Pi any the others managed to start on the ECU with some fairly common equipment I'm sure the SuperMonitor isn't going to be any trickier to find a reader.
Interesting fact: The USDM 7M-GE ECU has the operating code for BOTH the USDM and JDM 7M-GE's. Which mode it operates in is dependent upon certain resistor values. This is not the case with the GTE though. So, if you have a N/A and want to delete the EGR and operate with the JDM tune (safer given the higher combustion chamber temps) you needn't actually replace the ECU, just mod it quickly.
Like I said... crazy stuff!