I don't know anything about the HH3, however the requirement is that there is a WAN port, or a LAN port that can be configured as a WAN port.
A quick google suggests that the HH3 was a WAN port marked "GiGE" (Gigabit Ethernet) - you can proably confirm that by plugging a PC into that socket. If it *doesn't* get an internet connection, then it's probably a WAN port.
Someone with more knowledge of the HH3 may be along shortly
Cheers,
AP
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