Mirror puddle lights w/alarm?

I need some expert advice fast. I'm tring to make this mod work on my truck with my Mirrors Puddle Lights. I'm tring to have my puddle lights come on and off with my dome lights. I would like to do this when I arm and disarm my alarm. I have a Viper 791XV alarm and was wondering if I could splice into the alarm's Dome light output wire to use to trigger a relay to make this work. I have scetched a diagram showing what I plan to do.  

Thanks in advance

http://briefcase.yahoo.com/joeyhay99 

I have a 2006 Chevy Silverado Crew Cab.