Just adding these links for reference to the thread:
Variable Line Level Preamp Outputs From ACM (Factory Radio) For Amplifier Upgrades
2016 Ford Explorer Sport Build Log
- posts #20 and #32
Just as an aside, at one of the usual drop out spots on my commute I happened to look up and there was a cell tower in direct line of sight just off the highway. This seems to correlate with a lot of the data in this post so far.
According to this post on a Focus forum, the antenna change was supposed to address AM reception issues but also improved everything else.
I'm assuming that P/N 18936 is the revised antenna base you're talking about.
I'm certainly not trying to stir the pot, but I honestly think you've got a bad read on the Livernois team and that is unfortunate. If they came off as arrogant or disrespectful I'm 100% positive that's not what they intended. These guys are truly a class act and over-the-top customer service...