My Edelbrock AirGap RPM on my 396W stroker is leaking some fluid out of the very rear of intake at the bolt. There is a coolant passage on the rear of the heads that dead end into the intake mainfold. I'm sure the original intake had a passage way from one rear of head to the other side. There are 2 areas on the RPM that look like they could be drilled , tapped and a connection made from one side to the other. Have any of you guys done this? If so, what size hole, fittings, etc. Seems like this would allow for better coolant circulation.
Bob