I have the ppc 6800 as well for sprint and this does work for it. here's the post that tells you exactly how to install it. Also as I was told, some of these builds are carrier free so you would have to get the carrier cab for your service, a few posts above this you will see how to get the carrier cab for sprint
Thanks bbsandkm
http://forum.ppcgeeks.com/showthread.php?t=33857