When I take my 95 LS past 5,500 rpm or so, there's this squealing noise, kinda sounds like a turbo spooling up, and it continues until the redline. Anyone know what it could be?

Check your vacuum hose.

either powerband in full effect or maybe your timing belt is tight enough to start singing. Single cam hondas have that effect if the timing belt is really tight; you'll here a winding up sound.