6-18322 Pretty early TMCC I believe.. that explains it.
Doing more research...
Will the RL4C board from ERR add this capability? (from my reading it looks like the RL2C board is TMCC and the RL4C board adds legacy - but I can't find many details).
Basically I'm taking stock as to how much it will cost to update all my engines v.s. selling them (all are conventional control) and just buying a legacy engine or two..