Oh, come now, Jock!

While the information about the local laws is certainly helpful, you're spoiling the dream for us Americans!

You should wait and let your local midges do that once they've found their way up the "kilt flue"!

On a more serious note -

You'll find the topic of what "historic" Highlanders wore has been done to death on these boards, so I'll keep it concise. While many Highlanders did, in fact, wear kilts and other traditional items while working, hunting, etc., it seems that many (if not the vast majority) adopted more practical clothing for such activities.
From what Jock has said here and before, I imagine the activities that you're planning will be terribly uncomfortable in traditional Highland dress.
That said, if you're in it for the experience and memories, don't let anyone stop you; just be aware that you may end up with some memories you'll want to forget!

EDIT: Lovely photos, as usual, Jock! You managed to post them before I could get my response up.