I would ground the antenna bracket itself to the frame. Because we're dealing with RF ground, not electrical ground the large diameter wire is necessary. Even better would be to use ground strap. The large diameter wire or ground strap is necessary because RF travels only along the surface of the wire. This is called the "skin effect". So to put it simply: to obtain a better RF ground, you need more surface for the RF to travel on.
Hope that helps.
Moleculo
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Hope that helps.
Moleculo
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