300tdi Disco Alarm

I had all four the indicators flashing over the weekend ,I found the alarm unit above the passenger footwell clicking away . My dog had knocked the cardboard footwell cover and the unit had fallen down ,the unit didn't like being shaken or laying on it's side . I tucked it back up and jammed it against the foam block with a big lump of foam rubber and it's been fine since but it got me wondering , is there a motion detector in the green box ?
Living in very sparsely populated north east Scotland ,I really don't need an alarm and don't need the problems that could come from a dodgy alarm unit . My last old disco ,a 1996 300tdi didn't have much in the electric windows and only had three doors so when the alarm started to take the **** ,I dumped it ,lost the central locking , but gained reliability .wiring directly from the ignition switch . I can't do that with the current disco ,far too many electrical gadgets .
So , If I earth the wire from the starter relay that normally earths via the alarm ,can I ensure the alarm can't leave me stranded if it goes fubar ?

Yes you can, is just a standard bypass overlay, its done all the time on low voltage circuits, if the point of issue can not be found in the wiring
Detach the existing wire that's from the alarm ecu to the relay if you wish, you proberly will have to do that to enable access to the relay to terminate your additional wire.