As any Deadhead worth their salt already knows, the good ol’ US Library of Congress has massive archives that include master audio files [Betty’s direct mix in many] for dozens of their live shows. If you want to veer off into spinning around in the black lights while huffing on your bong, this is the place. Patchouli not included: https://archive.org/details/GratefulDead -click on: “Collection”
An interesting set of sessions with the band and Bob Dylan rehearsing pre-tour in San Rafael HERE.