Dude, thank you so much! They may brackets for the 07-14 GM 1500 also. The first I’ve found.
Nice find, 2003 compatible GM........VERY NICE
.......And because they are not sold under a 'Comm' gear category, you get 2, not just one. I mounted a future Antenna base on the left fender/hood location for a possible phone booster or for a comm install. As a "get it while available type find", AKA....You Snooze, you lose type of thing. At the moment I have a Wilson 5000 spring mounted on the left front bed location (CB, on a QR base), a NMO on the right front bed (GMRS)....3 foot, not a stubby,, and a magnetic roof top antenna that serves as a possible GMRS or as used as a adapted handheld scanner extension for use over the 'rubber ducky' H/H unit antenna.
I also did a accessory on the right front upper Bull Bar tab, that allows possible versatility(multi-use) on a future project write-up. This leaves me the upper L/F tab open for....SOMETHING
in the future. Thanks for the update, as those who follow the SILVERADO thread appreciate any gear updates that are found out there!