Gris,
I've checked out your page/setup in the past - how is the radio reception with this? Can you run the radio/CB at the same time? Can you use the stock antenna for the CB? (I know a CB antenna will have better range, but will the stock AM/FM antenna work?)
Radio reception improved with the Firestick. I can't say how much, but it's better. Quality is the same, but range has extended a good amount. Stations that used to stop the scan, but were really fuzzy are now clear and a whole new batch of fuzzy stations stop the scan that I never had before.
Radio and CB work fine at the same time. TBO, I very rarely have both going. If I'm on the trail, sure, but on the highway, if I turn the CB on, I usually want to hear what's up, so turn the radio down.
I don;t know how well the stock antenna would perform. I'm not so sure it would work. CB antennas are wound very differently than an AM/FM antenna that is just concerned with length. Also, a CB antenna needs to be "tuned". most have a small screw at the tip that can be adjusted up and down to get the exact perfect length. even the slightest adjustment will throw off the reception to the CB. I'd think that unless you got EXTREMELY lucky, there is no way that the stock antenna could be anywhere close to perfectly tuned.