Thanks for the link. I've been trying to work on this but not having a lot of success.
I've used WinSCP to connect to the ESXi host and then changed all references to port 443 to 4567 and restarted the management agents.
I've then tried to change the ports in the firewall config on the ESXi host to allow 4567.
I am still having the same issue and suspect that I am not making the correct changes to the config files.
I've attached them here.
Can anyone tell me if they are correct, or make changes and re-post?