P&K got their 105.3 gig from their lawsuit back in '99, which you can google for the details.
If you listened to the station back when it was called "The Talk that Rocks Texas", P&K had a crappy graveyard gig with no listeners. I actually enjoyed their show when they came on after Howard Stern, which is how they got most of their ratings. The shows was good back then and 105.3 peaked in that period. This was before the Janet Jackson thing, around '03 is when it peaked. Howard Stern was still good on free radio, P&K were enjoyable with Sybil, Russ Martin was still a fresh and somewhat original show, Tom Leykis was his absolute best in '03, Loveline was still really good with Adam Corolla. Everything seemed to click back then. Shows like Leykis were much edgier and hysterical... Suddenly, everything started becoming repetitive and stale. Not just because of the Janet Jackson Super Bowl thing, although it started going downhill after that debacle