09 Silverado rs/a install parking lights

I am about to do my first remote start/alarm install. I have been doing some research I have everything 99% lined out however I have a single lingering question. Everything everywhere says to use the light blue wire from the parking light switch, for the parking light output from the alarm. However, this truck currently has an autopage alarm installed(it was that way when I bought it) and the autopage is hooked up in that manner(light blue at switch). This causes the dash illumination to flash everytime the doors are locked, or unlocked. Would it not be more prudent/is there any reason I should not use the dark blue wire that goes from the bcm to the parking light relay instead? If I were to utilise this wire would I need to place diodes to prevent back feed since I am simply going to ground it at the alarm module??

Whether you connect at the switch or at the relay the effect will be the same. Switch goes to BCM which turns on the relay. Dash illumination will light up either way. No diodes will be needed as it is a ground trigger.

Even though I would be on the dark blue post bcm instead of the light blue pre bcm? looking at the wiring diagrams I dont see how thats possible?.

shouldnt the alarm just provide ground to the parking relay thereby providing power to the parking lights only and bypassing the BCM altogether? I believe the BCM provides a separate output for the dash illumination?

Typically the parking light output from BCM on newer vehicles is a multi feed output. Will back feed the other tied negative triggers. You can test it and if it doesn't flash the Dash lights and it's that important to you to not have them flash Then connect it there. Otherwise you would need to cut the blue wire and diode it with the band towards the BCM and connect the alarm after the diode relay side.
But if its already been hooked up to light switch why modify more wires than have already been.

So I completed this install several months ago, in sept shortly after I started this thread, Just thought I would update. I ended up using the dark blue wire that goes from the bcm to the parking light relay, connecting at the bcm where I was already connecting several other wires, this did have the desired effect with no side effects, I recommend this to any who maybe doing future installs. As I previously stated, this will prevent the dash lights from flashing with the alarm every time the parking lights flash. no diodes were necessary.