Any immobiliser experts?? Selca immobiliser fault

My golf has had what I can tell a selca (IM3.22 model possibly?) fitted a long time ago, not sure if dealer fit or aftermarket as they seem quite popular back in the day, The touch socket for the fob works fine and everything but the LED no longer flashes, the socket has one red and one black wire on one connection firther down and one single grey wire on another plug further down the loom, I can't find a wiring diagram anywhere!!! I've traced the wires and they go up behind the fusebox so would have to drop that down but with zero info I've not got much to go on! I also only have one red fob (master I think?) and spare parts seems impossible to get for selca if even available anymore… Was considering removing it and replacing with new but without any ideas I might have a right mare taking it out! I assume it will have 2 cuts possibly starter and maybe another ignition circuit? (My car is carburettor not injection)

If anyone is clued up on this please give any info you can as I'm paranoid it's going to pack up and leave me stranded! Picture of new kit for example

   

Not much help I'm afraid but I can tell you this much, I honestly don't believe that one was a dealer fit back in the day.  

Golf Cabrio said

Not much help I'm afraid but I can tell you this much, I honestly don't believe that one was a dealer fit back in the day.  

 Possibly not I just wasn't too sure as they're fitted to some other cars a lot and from what I can see it's a very well and properly done install,, which makes life even harder for me!

emailed a local specialist today for a quote to remove it I wouldn't attempt that myself without wiring diagrams but I'm competent to test it at least, I've disconnect the one grey pin from the socket and it made no difference to the function so it must be for the LED, I'm gonna power probe that line and see if it lights up, if it does then my immobiliser/line that side is faulty, if it doesn't then LED or line that side is faulty, that's the plan anyway! 

Cheers mate been flat out trying to get it finished then I'll worry about it when I have time to! 

Fixed it! Got the multimeter out and checked voltage down the line I suspected was for the LED and found it pulsing, found a led in the dash switches wired to nothing and tapped it in and it works! So I ran new wires up from the immobiliser to the dash and voilà! Love a neat bit of handy work, now need to try and find a new spare fob