Stephane Grappelli is on "Wish You Were Here" (sort of)

First, quick correction: he’s a jazz violinist, not guitarist. But yes, he recorded a violin part for the title track of Pink Floyd’s Wish You Were Here album. The band ended up not using it in the final mix, though. Some copies of the session tapes exist, and you can hear his contribution on the 2011 Immersion box set