I'm changing the pots in my Gibson LP with P90s to 500k and I figured I'd see how P90s sound in series before starting the task because it may be a sound I can use, but I can't find a single sound sample of this anywhere. And I've checked numerous forums but few people have done it and no one paints a clear picture of what it sounds like and if it's even worth doing.

I'd really like to hear a sound byte of this in action, but if someone has done it and can vouch that it's a worthy sound, then I'll go ahead and go for it.
I've done it once with stock Epiphone P-90s. It's pretty beefy. It sounded and reacted like the most retardedly overwound humbucker ever. Part of that I think is because of the positioning. I think a bridge + middle P-90 in series would sound brilliant but bridge + neck was so incredibly warm and hot that it was impossible to keep clean and it was a totally muddy mess the second I put the gain up at all. I remember the output measured out to be more than an EMG 81. It did sound really nice clean though, for a kind of jazzy, ultra-smooth tone. All mids, a lot of bass and virtually no treble.
Add a switch to toggle between series and parallel. If you dont want to cut a new hole, use a push/pull. For $5 you make it one and a half times as fun.
Ok, so it doesn't sound like anything worth while. Grohl1987, I actually saw a thread somewhere else where the guy had two P90s in series, right next to each other by the bridge, and he said it was clean and sounded like a meaty humbucker. I guess if I had that configuration, I'd go for it, but it's B+N, so maybe not.

I thought about adding a push/pull. I did it on my strat, it wouldn't be hard to do at all. I just don't feel like messing with it though if it's not worth my time. I kinda want this Les Paul to go for simplicity, since all of my other guitars are wired in weird configurations. I appreciate the replies. From the looks of it, there aren't many people that have done it, so it's probably a sign that it's not worth doing.