To be honest, I wouldn't recommand that, for the simple reason that Kab warriors looks like freakin' stormtroopers, even if this looks like a gorgeous idea on paper...
But don't get discouraged ; if you really want to do it, you'll do it
Anyway, I went for a similar scheme but switched black for red after a 5 man squad of kabs painted.
I went random on the armor for the secondary color (shoulder pad, knuckles, knees, etc.) and always between 1 and 3 per guy and I find the result pleasing to the eye and homogeneous.
If you want to have the same color at the same place for everyone, I'd recommand testing your color scheme before, first through pattern ( http://4.bp.blogspot.com/-Wfn_glgMTks/UQfVdMhd_tI/AAAAAAAAD-c/DSL-VI-OQuc/s1600/scanne10.jpg ; looks for blanks ones, they are some, but was too lazy d: ) and then test it on a couple warriors.
Also consider neutral bases to valorize you color scheme (desert, jungle, mars) ; with such a typical color scheme it's pretty important and must be chosen before.
Hope it helped, feel free to ask more details, and have fun painting.