A Bill Murray Challenge: Rushmore Mystery Cache

This cache is at the posted coords but you must first complete the following challenge to log this cache.

This is a series of challenge caches placed in honor of my favorite Bill Murray movies.

Let's return to school and learn your ABC's

Before you log this cache as a find you must meet the following requirements:

• Have found a cache starting with the letter A
• On some date after that, have found a cache starting with the letter B
• On some date after that, have found a cache starting with the letter C
• ...
• And finally, after all those letters, have found a cache starting with the letter Z

 Here are a few more details:

1. Only the first character of each cache name will count. Caches whose names start with non-letters (digits, space or special characters) cannot be used towards this challenge.
2. You can have any number of cache finds between your qualifying finds. So you can find E C U Y A D 3 D M K 8 ( C A B J S 9 M Q - D C L M B D E ... you can count towards your challenge the A B C D E that are in bold above. Other cache finds in the sequence are simply discarded.
3. You can only qualify one letter per caching day. If, on the same day, you find a cache starting with A and later that day find a cache starting with B, you cannot count the B. You have to earn your alphabet slowly, one letter per day.
4. You must demonstrate that you meet the challenge. You can do that by including in your log the list of qualifying cache GC codes (and preferably also cache names and the dates you found them), or by including a publicly accessible bookmark list of your qualifying finds.

Thanks to SeekerSupreme for the idea.