Thanks for everyone's replies.
I appreciate them all.
I'm to a point where I have almost given up on the yellow shirts.
What I was looking for was a tee or polo made of cool, stain resistant fabric, or one that was treated somehow.
What I ended up doing for the time being was just going green. It looks great, but my shirts are logo-free. The Lesco green is a sharp color... nothing remotely like what you see on their website. But at the same time, the Lesco green is a shade of it's own. It's close to many shades, but not the same. Shades such as John Deere green, athletic green, street sign green, ect...
So you can imagine it is hard to attain that neat look of uniformity I prefer. I finally ended up finding an acceptable color of green shirt at Old Navy. It's a blank single color tee, but a stylish one with a seam across the chest and so forth. The color and the fabric is not naturally real hot, but just like all Old Navy tees, the fabric itself is thin and very soft. So it gets sticky, clingy and hot as a result. Once this happens, the stylish design of all the seams becomes a torment. In the hot weater we have here, they will tear you up. I've had my biceps nearly raw on several occasions.
So.... I guess unless I can find some other source for shirts the shade of green I need, I will just have to break down and remove the non-conforming colored parts off the Lesco and repaint them... eXmark Red...
But of course, my wife strongly objects to this.