Ok! Almost in business.
I can convert NMEA to TSIP and it is usable by the Trimble ez150!!! The 150 really has no security other than protocol ambiguity. No TSIP handshakes needed.
But the Ez250 requires some special connection sequence to an external tsip reciever. I have found a very cheap slightly smashed ag252 receiver. If it powers up i should be able to replicate the log in sequence.