Just wanted to post an update and solution to this in case anyone down the road wonders the same thing.

With the help of a forum member, my cluster was "programmed" to turn on the ACE light and now it works just as it should. Very strange to me, but it looks like even if your truck is equipped, if you replace the cluster, it will need to be configured to recognize the ACE system or the SLS system for the warning lamps to turn on (if the donor truck did not have those systems).