One of my favourite "after school" viewing pleasures when I was a kid was The Partridge Family, a half-hour musical sitcom detailing the humorous adventures of a family trying to make it as a rock group. This cache was placed in honour of Danny Partridge, the smart-aleck of the family, played by Danny Bonaduce.
One of my favorite episodes: Danny goes on outings with each of his siblings to do something they like, and then it turns out that in each case he was getting to do something he wanted at the same time.
In order to find this cache, go to the posted coordinates and project a waypoint as follows: Look at the metal tag on the telephone pole where you are standing, and take note of the vertical 5-digit number. To get the bearing (true north), take the numeric value of DANNYBONADUCE and multiply by 2, then add the two digit number formed by the 3rd and 1st digits on the metal tag. To get the distance (meters), take the numeric value of REDHEAD and subtract the two digit number formed by the 4th and 1st numbers on the metal tag. As a check for your projected waypoint, here are the last digits of the north (5) and west (9).
Since this is a letterbox, please leave the stamp behind, and be careful when peeling back the flap where the log sheet is stored.