Set Test Socket during Interactive Mode

I'd like to execute a single step using Interactive Mode on a particular Test Socket that I specifiy. In order to do this I suspect that I would set RunState.TestSockets.MyIndex prior to step execution (may preinteractive callback). How can I implement this without adding preinteractive callbacks to all subsequences? Adding a preinteractive callback to process model does nothing since the process model is not used when performing interactive on a subsequence.

Any ideas?