Bob:
A lot of people have disconnected the tap tower from the top of the Kegerator and mounted it on the bar top.
Be sure that you can remove the tower before you buy. If ordering online, go to a local store first to scope them out.
You will need to use some spray insulation foam to seal up the hole, or better yet, just extend a PVC tube down the bar top hole right into the kegerator, then run your beer line through the PVC tube.
Finally fill around the PVC tube with spray foam insulation (you can jacket the smaller tube with a larger tube to contain the insulation). The idea is to keep the beer line cold all the way up to the tap.
The other option is to notch the bar top to allow the tap tower to slide into place.
Check the Builder’s Gallery for ideas on how other have accomplished this.