Thanks for the link. These are the steps that I tried to follow as best as I could and wound up with the issue that I mentioned.
Fiddling around with things a bit more, I found another piece of info that led me to the source of the issue. So once I had my VM powered on with the Serial Port configured as mentioned in my original post, I looked at the VM settings. When I select the Serial Port, it's set to connect at power on, but the Connected box wasn't checked. If I check the Connected box and click OK, it gives an error.
Serial port (serial0) connection control operation failed.
Searching for that error lead me to a forum than then revealed that I need a full Enterprise license to support remote serial ports. I only have essentials.
Bummer! At least I know now and maybe others might stumble upon this. I sort of wish it would have given me an error at the time of adding the serial port to inform me of this.