Elwyn -

Don't think you're right about JPB. Plus, Paddy Driver never started a W.C. GP. Practiced a Lotus 24-BRM and qualified 24th in 1963 S African GP, stuffed it late in practice and non-started.

Tino Brambilla never did a W.C. GP, while brother Vittorio never did a TT.

Marco -

See above for Paddy Driver - you are of course right about Seppi Siffert.

Keith Campbell entered the 1958 Monaco GP in a Maserati 250F, but didn't turn up.

There is one more - Roger Loyer. Rode Velos pre-war, and drove a Gordini in the 1954 Argentine F1 Grand Prix.

Something's nagging at me about one more, but I can't remember . . . . . . . . .