LS2 wiring and cooling question

[kochevy67]

I was hoping someone could answer my questions.

1. I was wondering if the small fitting on top of the head that has a hose which crosses from side to side could be removed and plugged like the two in teh back near the firewall. These are the fittings that are at the front of the motor and seem to connect the cylinder heads, probably to prevent a hot spot or to help with air pockets.

2. I am installing an LS2 from a 2006 GTO in my Chevelle. There is a white square plug in the harness near the computer connection, it has 13 wires going into it and I have no idea where it goes. I am running the factory harness and have everything accounted for except that. I think it may be for the factory gauge cluster but I am not sure. The plug is about 1in. and 1 1/2 in.

Thanks