I just learned recently that this was possible at my little airport,
Hawthorne CA (KHHR). Presumably they get a squawk for you from SoCal and
arrange your radar coverage. Couple questions--

1. What is the phraseology of the request to ground?

--I'm guessing it's just "ground, cessna 1234 can you arrange flight
following to xxx via y and z"

2. At what point would you contact SoCal, and what would your initial
callup be? I assume you don't "request" FF at that point since it's already
been arranged, but I can't figure out what's best. Would you just report in
as you would if you were being handed off to a tower or tracon controller?