FINALLY!!! I have just successfully done the install. The trick for me was getting off that grab bar. I thought those plugs pop off to reveal a screw or something, but that wasn't the case. I got them started all the way around and then gave them a good yank like you said and off they came. Then I could see the track behind the A-Pillar and fished the antenna wire through. Thanks for all the help PhilD! Now I'm all set.
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'03 Hummer H2 Adv./Lux. Pkgs. Sunset Orange W/Sunroof
Air Spring Susp. Pkg. + 3rd. row seat & DVD System.
CompuStar Auto Security/Remote Starter.
http://www.haugens.com