In an episode of the popular comedy series 'Frasier' entitled 'Door Jam' the characters Martin Crane (the father) and Daphne Moon (housekeeper / psychical therapist) watch two episodes of 'The Rockford Files' (which Martin simply refers to as "Rockford"). The first episode they watch is the Pilot (described as "the first ever episode"). As they watch the Pilot Daphne comments that Martin looks like Rocky (John Mahoney who plays Martin Crane does bare a similar resemblance to Noah Beery Jr but not to Robert Donley who actually played Rocky in the Pilot).
When mentioning the second episode they watch Daphne says; "Tom Selleck guest stars". However, the Frasier episode also refers to the fact that The Rockford Files was filmed in Malibu (Martin Crane gives separate trivia on the fact that comedy series 'M*A*S*H' was filmed in the Malibu hills area). However we do not see exterior shots of Jim's trailer at Paradise Cove in White on White (nor incidentally in the Pilot because the Trailer was not situated in Malibu at that time). There is one quick flash of an aerial shot of the trailer at the Cove in the sixth season episode 'Nice Guys Finish Dead', but it is not obvious that it is in Malibu.
In an strange coincidence to the above, this episode is also referred to in an episode of 'Magnum PI', entitled 'Tigers Fan', where two guest characters are talking about "Last nights Rockford Files which featured this Lance White character". We know of course that Tom Selleck was Lance White and that he went on to became Thomas Magnum!