I have, essentially, done the same except directly on the Gazeteer. I think at this level, given that one does not go out on a Saturday and do the "Delorme", manually is fine. I can see where if a cache is close to the border of the grid it could be difficult to determine which grid it is.

Originally Posted by
Sudonim
I used and marked the actual DeLorme Gazeteer and photocopied the back cover, crossing off maps as I went.
Everyone has the right to be an idiot at times. Just don't abuse the privilege.