| The connection for the diagnostics is a three way AMP multipole connector tailed out of the ECU plug.
The mathesis connects into this.
The diagnostic software I have connects here to, via the 9 pin serial port on the PC.
Mathesis are very hard to get a hold of unless you are an authorised dealer. I got mine from one that had closed down a couple of years ago, and even then, the software cards I have only go to 2001.
I use the PC for most of the static stuff in the workshop and the new ECU's. The mathesis comes in handy for mobile work and setting the TPS etc. | 
Threaded Mode