Thought I would start a new thread for this.
Over on BeechTalk, there has been information presented about recent changes to installation of the G5 (which impacts installing the GFC500 too). Apparently in the G5 installation manual, revision 16 (and now 17 as well), installing a G5 now requires installation of a resister and diode (no big deal) but also requires use of Carlisle CAN24TST120 wire for all CAN buss connections. Unfortunately this appears to be made of unobtainium (almost). There have been reports of it being found in small quantities which by now I'm such have been snatched up. 100' at $10/foot and somebody else found 125 feet and took it.
Anyway, supposedly it is going to be very difficult or impossible to find until July sometime. So if you are like us, with an upcoming G5 installation date (April 22nd for us), you might want to make sure your installer has the wire in stock before you let them rip into your airplane. If they ripped into ours in April and then found out they couldn't finish the job until July or August, I'd be pissed. That's almost the entire good flying season in this part of the country.
Our installer is checking into it but has not called me back yet.
Fore warned is fore armed.