How do I make a custom date format to be "MMM DD YYYY" in uppercase?

I tried doing custom format, but it only allows lower case.  I would like "Sep 21 2016" to read "SEP 21 2016".  At the same time, I am looking to validate it so that this is the only acceptable data in this field.  I am still quite new to Adobe pro, but I know where to put the javascript for formatting, validation, and keystroke.  I have done a lot of searches but I can't seem to find the solution that takes a date and makes it uppercase while still validating the actual date.  In a perfect world, I am also hoping that before a user types anything in, I would like to have the format of the date box be visible until they start typing, but in a gray font.  "MMM DD YYYY".  Is this possible?  Any help is greatly appreciated.