The band POPDeFECT made a Facebook post with a couple photos about a gig they had played in San Francisco. They remembered only that the band Paper Tulips and Beck opened for them. (All three had records on Flipside at the time.)
Some research turned up an ad in an SF paper for a show they did in May 1992, though it does not mention Beck. It was at the Chameleon.
Whether there more shows on a small tour or just a one-off night together in San Francisco, I do not know.