New motor won't idle right

So I have a new engine in my car it's a 7mge running on 88 turbo electronics. I have a wideband installed and it hovers around 12 when it idles and it's a rough one sounds like a cammed v8. I was thinking a vacuum leak but I have all the egr removed so most are capped. Also there is a medium sized hole on the gte throttle body on the top. Is that where the coolant line ran ? And do I need to cap it to fix the idle ? Also thinking maybe the throttle isn't set right so it idles ? How high should the screw be?