I've found that most bikes out at this elevation don't like the 27.5 pilots. Also most bikes out here seem to run best with the needles second notch from the blunt end(top).
To give you an idea I run 310 mains, 25 pilots, needles second notch from blunt end, air screws 1 1/2 out. In the middle of the summer the 310's are even a tad rich, but I like running a little richer than too lean.
I have a stock stroke, aggressive dune port, CPI's, vforce3's, k&n pods, +4 timing, 19cc domes....etc.
Have to looked at your plugs? I would put 25 pilots in, and move your needle. I don't have any experience with t-5's, everyone I ride with up here pretty much runs CPI's. My guess would be your running rich though.