I tapped a fitting on the lower part of my block behind the turbo and ran heater hose up to the neck where the thermostat is.
Is this the same thing you are talking about?
I split the line and am using it for the cooling lines on my turbo now?
There is just no regulator there

 

They take the heater feed off the head near #5. There is a whole row of 1/2"NPT plugs along the top of the head. This is not my current setup. Currently, a better valve for the heater shutoff is up on the firewall by the filter:

http://stuff.is-a-geek.net/PhotoAlbu...ics/CRD_30.JPG

The common rails are known to blow freeze plugs at high rpm due to water jacket pressure, which can be relived by opening up an additional port back there as well as provide increased flow for cooling. They have always all run hotter on #6 due to this.