I bumped into those Five Guys Named Moe again last night. They were telling me about their latest exploit, a 45 cache power-trail. Sounded quite interesting - they've managed to squeeze all of the caches into a square mile, and the distance between each cache is exactly the same, from one to the next. There's also a bonus cache - there'll be bonus info in the caches along the trail, but they seemed to suggest that you can work out the information you need just from the positions of some of the caches. Wish I'd paid a bit more attention!
They were off to hide the bonus straight after our chat, but (once again) they left an interesting scrap of paper behind! I assume the grid represents the area where they've set the trail. Not too sure about the letters and numbers. The coords below must be for the bonus, but unless they were heading off to Mali, there must be some other way to read them.
The scrap of paper
Do you think we have enough information to find the bonus cache before it's published?
Congratulations on the FTF to colincactus.