Here are interviews with Bill Bixby and Ray Walston. from the 60s.

There are 2 interviews with Bill here, from 1965 where he discusses "Martian" and another from 1969 where he talks about "Courtship of Eddie's Father"

http://major-smolinski.com/NAMES/BIXBY.html

Ray Walston's interview is from 1963, prior to the premiere of MFM:

http://major-smolinski.com/NAMES/WALSTON.html