regular heater/ac controls to dual climate controls

Can a regular heater control be switched to dual climate controls on a 1999 GRAND PRIX SE? Has anyone done this? Thanks.

not in any kind of practical way. It would require a complete disassembly of the dash, and replacement of the entire HVAC unit to do so. This would require a complete donor car and a whole lot of time and wiring. I guess if you REALLY wanted to do it, but the ends wouldn't justify the means.

Thanks for the reply.