Trunk Relay Assistance Needed?

I have just installed a Prestige Platinum APS 996 in a 1995 Mercury Grand Marquis.  Everything is working just fine with the exception of the trunk release.  I hooked up a relay using the wiring detail in the installation manual, which indicated the following.

pin 86 - dark blue wire delayed 300mA pulsed of alarm, pin 85 - fused 12volt source, pin 87 - to the vehicle trunk release (purple / YELLOW) wire, and pins 87a and 30 - fused 12volt source since this vehicle circuit switches 12volts when the trunk button is pressed.

I did notice that the (purple / YELLOW) wire is unusually thick, which makes me believe that I cannot simple tap into the wire.

Any suggestions would be greatly apprecitated.  Thanks

well, i just finished this on my 97 Crown Vic (did not have keyless OEM, just power locks)- if yours was the same as mine, you do NOT want to cut the purple / YELLOW, just tap into from 30 on the relay.  My Rattler 369D instructions and their tech support told me to cut it and wire one side to 87A and one to 30.  Alarm pulse to 85 and 12v+ to 87 & 86.  I did it this way, the remote would pop the trunk but now the dash mounted button would not.

I followed David's advice (Ace Security) and wired it per http://wiringinstructions.com/231.htm (I had to reconnect the purple / YELLOW that I had cut).  Now it works perfectly- both the remote and the button will pop the trunk.

I have no idea why DEI tech support tells you to cut the wire, all that I know is it wouldn't work that way...  Hope this may help since our cars are the same wiring...