Ron, I keep looking at the tartan and I think green would work with it. Yellow plus black equals green. There's a whole range, from bottle to dark olive up through a lighter celadon that would look sharp. A green shirt that is light enough to draw a bit of focus away from the yellow, black hose and red flashes. Or vice versa: black shirt+light green hose. Also you can have a red shirt or hose that is a bit washed out--weathered almost, so the red is not "clashing" with the yellow but accentuates it.

I know this seems a little far out but I have lots of colors in my head right now. I am fortunate enough to have a mother who knits hose for me, I just got off the phone with her choosing the next color.

Moosedog