I got to thinking about multiple house codes with a standard IR543 and I came up with a pretty easy mod to support 2 house codes. I used a Universal module's relay contacts to modify one bit of the codewheel setting on the IR543. I did lose one unit code on each of the housecodes. I set the Universal module to housecode "I" with unit code set to 10. The IR543's housecode wheel was set to "I". Sending "10" "ON" from the IR remote sends I-10 I-ON, activating the Universal module's relay contacts, shorting the IR543's h2 codewheel contacts. This modifies the IR543's housecode setting from "I" to "G" for all subsequent commands. It's a bit tricky to send the "OFF" command to the Universal module using the IR543 at that point, since the Universal module is still on housecode "I". Defining a CM11A macro to send I-10 I-OFF, when it sees a G-10 G-OFF, solves that problem. So, "10" "ON" from the IR remote, selects one housecode and "10" "OFF" selects the other.

John Galvin