Well, I have decoded the datastream in theory. Just some good bedtime reading (I lied with good, more like reading for insomniacs ) of the 6803 programmers manual and head banging with the several chips I have disassembled

So I now just (JUST!!!) need to put the practice in to motion and log the datastream to a PC and verify the output.

Then it's a case of coding a PIC Eprom chip to decode the datastream and output the info to the LCD. It's been a while since I did any of that stuff so don't know how long that will take

Jeez I make it sound so easy! In reality it may take some time

Will keep you informed of any progress.