relay control of indicators for disabilit

Hi I am disabled & have been using a 10 relay IR setup to override indicators/horn,high beam etc, by putting relays in parallel with corresponding switch. However I am unsure how to wire this car(BMW E46 UK) as it is the canbus? wiring,(have been told that if i try to wire as normal it will fry very expensive bits). From looking at wiring diagrams of indicator it looks like the switch changes the signal by using a resistor?-is this correct & does any one know the value. Any help with this would be greatly appreciated as my only other choice is to get a "disability approved" garage to rip me off for about £1200. (almost more than the cars worth!) Thanks in advance

None of the above are CAN are all doable with relays, the indicators use diodes after the relay, 3 per side. No way am I going to explain this to you right now, it would take me less time to do than to explain. My guess is for the above mentioned items about £150 labour plus mileage plus parts.