Yup ... You gonna need the AS ETH 5PXG ...
http://www.humminbird.com/Products/AS-ETH-5PXG/
Then both units and the iLink will connect to the AS ETH 5PXG ...
Your iLink should have come with an Ethernet cable...
And you will need an Ethernet cable from each unit to the AS ETH 5PXG ...
The AS ETH 5PXG requires 12v power so plan it's installation ...
Rickie