duuuuude. as a moderator/poster on multiple communities, i have seen my fair share of double posting..
but a triple?! that is the first in a while.. there is an edit, or modify button.. you can use that to add content to your previous reply. generally, it is considered good forum etiquette to not "double post" in the same thread, instead you should edit your previous posts to include what your subsequent additions would have contained
as to your original query, i usually wear all tan dickies, with my boots and tac gear. it has never been a problem, i'm sure you can get away with doing that as i do.
but..i mean, don't wear like, khakis and a tan tshirt... i would recommend a dickies long or short sleeved work shirt, and a pair of dickies work pants, they are about 15$ each at wal-mart if you really do not want to invest in a battle uniform at this point in time
of course, this is all speculation, the event organizer may say otherwise.