How about:
Pilot: "ATS, Callsign, Request ATZ Transit"
ATS: "Callsign, pass your message"
Pilot: "Callsign, Type, (From, To), Position, Altitude, ETA overhead"
Best not to
request any
clearance from a FISO or Radio, only request a FIS / service.
I'd do it as per tmmorris's example.