Older CP Flight MCP737 setup

Hi Everyone, Just getting into the hardware side of things with my Flight Sim. I have FSX Steam and PMDG 737. I bought a used CP Flight MCP737 and it's the older Serial port model. I have done some reading and bought PSUIPC4. But trying to get it to work with my FSX 737 or my PMDG 737. I went to CP Flight and installed the drivers. When I run the CP Flight test software it changes everything. So it's talking. Just not in the Flight Sim.

Thanks,

Brian