After some google research, it appears the sways from hellwig (7743) fit on a '21. Some changes on suspension, but bar still fits the same. I ordered the one for 0-2" lift since our block is right around 2".
Supposedly a simple install, will report back. It's on Amazon btw.
Btw just picked up the truck with the SPC UCAs, RC2.5 fronts, and vertex rears. Couldn't take pics because it's pouring rain but so far It drives GREAT. Significantly better than the level kit, and stock rear shocks. They said it all went on no problem, aligned perfectly.