I have an EZ-V Minute Mount plow off a 2008 GMC 2509HD and I am trying to put it on a 2015 Ford F350. I have purchased the push plates, and I was told I had to have a 3 port isolation module instead of the 4 port one I had. So I got a 3 port isolation module and headlight connectors. My question is how do I hook up a 3 port module. I have an extra plug that was plugged in on the 4 port what do I do with that and which one goes into the 3 port module