The parts department where I purchased the Camaro is looking up the GM supplied auto dimming mirror part number along with the homelink part number.
There is no homeline/onstar/auto dimming mirror made by Gentex. With that in mind, all I can do is add the auto dimming feature via the mirror (of course) and the homelink is a separate panel/module in the headliner.
I'll post all of the info I get on this topic as soon as I get it.
12 Charger SRT8 | 04 Chevy SSR | 04 Ford Thunderbird PCR #428 | 06 Toyota Highlander Hybrid