Won't fit, even if it did the 6" tube won't really give you decent bass. Search for a thread I did, something like "another sub option for doublecab". I got a low profile JL Audio 8" in a box that fits perfectly under the rear seat and puts out good low bass, but not ear ripping loud.
Yep, me too. My days of booming bass are long over! I'm a drummer though, so I like to hear that bass guitar and floor toms and bass drum. The JL sub hits a lot deeper than you'd expect, but you can adjust the bass on the radio and the amp. My bass is turned all the way down on the radio and sometimes its still too loud for me. I need to get on the amp and make some adjustments too.