Wanted to share some of my experiences with dying tonight...
I got the RIT pearl grey and did my soldier story jumpsuit. I had used about the half the pack of grey with about 1/3 gallon of hot water and about a teaspoon of salt.
It came out very grey, far too grey. Luckily I had also gotten the color remover, so that instantly brought it back to normal.
I again tried the grey, but much more diluted. It's still drying, so well see how it turns out. At this point it's hardly noticeable. I think you might have to use the color remover first to achieve the desired hue, but at this point that's not something I want to try on my only jumpsuit.
I also tried to remove the color from the tan web belt with no success.
I then tried to dye it grey with no success. So that will probably stay tan. I might try bleach, but again at this point I'm not sure, I don't want to ruin anything.
So just a heads up for anyone get ready to dye their jumpsuits!