How to constrain a face but allow rotation

How can you constrain a face in translation but still allow it to rotate in Algor? I have looked at using the remote load tool which creates a relationship with a point and line elements to a face, which I can then constrain just the point. You then have to add cross section properties to those line elements. Seems, kind of odd that you are creating other parts just for constraining. Also, look at the universal joint tool. Anyone know what the best method is, or is there something simpler?

For example, a cart with casters you would want to constrain the caster plates in the direction of gravity but allow them to rotate and bend when it is loaded.

Any help would be appreciated. Thanks