Ok So this post inspired me to go listen to several months of 1995 (in order) between January all the way to 11/1/1995 (which was Billy's last day).
I noted a few subtle things that I hadn't remembered, but a few of you have touched on some of these.
Billy wanted to go to 5 days. After Ren & Stimpy was announced cancelled, Billy wanted the job security. Howard ripped him on air and appeared cold to the idea, saying that 3 days a week was enough Billy.
The John Kricfalusi ambush... Originally set up as a mystery guest, Billy ran into him in the bathroom before the segment and it went downhill from there. I don't know why anybody would call this "radio gold". It was awkward, mean spirited, and had me squirming every minute. I'm CERTAIN this soured Billy's relationship with Howard, though I'd love to hear what Howard's reasoning was for doing this at all. Howard was going through a really angry phase at this point... some of that stuff with Mancow was cringe-worthy.
Howard becoming #1 in Dallas... Now THIS I had never seen mentioned, but I am personally certain that a part this event really pissed off Howard... In the days immediately following Howard becoming #1 at the Eagle in Dallas for the first time, Howard did his typical chest-thumping, and read a news article from Dallas about the accomplishment. The news article credited Howard's accomplishment, but as a tagline, mentioned that the TRUE TALENT on the show was the unsung Billy West. When Howard read it, you could tell that it caught him by surprise. Robin would hand him a lot of stuff un-screened. In the following weeks Howard became increasingly "snappy" with West, sniping at him under his breath. In one instance Howard tells Billy to stop improvising and just stick to doing voices... Another instance Billy laughs at one of Howard's jokes and Howard calls him out for "forcing" the laugh. Billy defends himself by saying he genuinely thought what Howard said was funny. Howard grumbles that "I don't need you". Lastly, right toward the end, at the VERY end of a show in October, Billy is doing a great Jay Leno, and Howard makes a comment "Jay why are you and your wife negotiating for LESS vacation?" and Billy answers in Jay's voice "Job security".
The Indemnity clause... fucking Tom Cheapasano and K-roq... Mel Carmazin... They wanted Billy, in his contract, to assume personal liability for any lawsuits coming from anyone suing for the voices that Billy impersonated. FUCK THAT.
Interestingly, Billy's last two days, the 31st and 1st, were AWESOME, and some of Billy's best work, with Howard laughing it up just like everything was fine. One week later (11/7), after the release of Miss America, Howard makes a nasty reference to Billy as a "person he couldn't care less about" to Fred, though he doesn't bother mentioning him by name. Billy also got little mention in Miss America, though Howard blamed that on "time constraints".
In conclusion, I DO believe Howard had some beef with Billy, and vice versa... We'll never know the full dynamic, but the fact that he's never been back live is telling. I also think Violet West (Billy's wife) had some falling kind of out with the group, as she vanished from the show after that awkward manufactured "feud" bit with Allison Stern.