How did you you mount your CB antenna on your aluminum F150?

I found a truck bed stake pocket mount by Firestik that uses a flat metal piece that will stick out from under my tonneau cover for about $20. Next question. Antenna height vs. drive through? Tall as possible is best for the radio. Firestik makes them in 2, 3, 4 foot, etc. lengths. At a glance, 3' might work on the bedrail. 2' is a bit short for range. 4' will likely slam into every drive through limiter.
Thoughts? BTW, several decent new auto CBs for under $50 on Amazon.