Yes, I have heard a legal ID on KNFL. Please see the thread I started in the Salt Lake-Ogden-Provo section about KNFL. The legal ID consists of nothing more than "KNFL, Tremonton" spoken near or at the top of the hour, so you might miss it if you blink. Also, the audio on the legal ID is not very loud as compared to the volume of the music, so it's easy to miss--especially if Bob Dylan happens to be croaking out one of his raspy Christmas tunes when the ID is given.
A legal ID was heard at 8:30 PM tonight (with the usual low audio level)--so maybe now the station is identifying on the half hour instead of at the top of the hour?