Gandalf23 gives us this link.
Found this while searching for "Fighting Load Carrier" on google:
It's a .pdf from Specialty Defense on their MOLLE2 gear's care and use. It's got pictures and how to attach and adjust all of it. Pretty nice little pdf.
And courtesy of Randy K., I now have a pdf copy of the 1985 version of FM 21-15. If you would like for me to email it to you, drop me a line at GeorgeMason1776@aol.com.