Forgive me if i'm going over old ground here (I did try and read the whole thread).
I think one the most psychedelic records that i've heard has to be Slip Inside This House by the 13th Floor Elevators, those lyrics and that guitar.. It wasn't till a while after experimenting with drugs as a young teen that I started listening to music under the influence and I have to say it certainly opened a few doors (sorry).
I remember first listening to Gong after a heavy hot knives session, just sitting in the dark listening to Flying Teapot, I was hooked.. A few years later I remember listening to Sonic Boom's Spectrum album after drinking rather too much magic mushroom wine, it was incredible the kalidoscopic effect of the music rippling through everything around me, blissful in it's simplicity. I made the mistake of putting The Orb's Adventures Beyond the Ultraworld on which just took me away, completely. I think that my brain was assimilating everything in the music, all the complex samples and sound effects, which all contained there own unique stamp of history/memory, with all this unraveling all around me, with the added bonus of negating time and wrestling with Satan/God/sanity.
some other psychedelic bands worth mentioning - Butthole Surfers, Terminal Cheesecake, Legendary Pink Dots.