Well make sure if you wire in the new alarm you use bosch relays as it needs to hold the locks for 3 seconds to allow for pproper opperation. If not you may burn out the vacuum pumpp. Also make sure to totally disable the old alarm correctly or you may not be able to start youre car. Hop on over to benzworld dot org as I am pretty sure it was there I saw a great DIY on doing just that.

Be wary even with the proper relays the insullation may not hold up, mine was melted in alot of places when i removed the PO after market alarm.