I am running a heater core and A/C from Vintage Air, although with their system, the water flow to the heater is either fully blocked or partially blocked depending on the control setting of the unit.
I'm going to drill 3 - 3/16 holes in my thermostat to ensure enough flow to compensate for blocking that bypass hose on my engine. The plug is hard to see, but if you are able to zoom in, you can see the edge of the plug in front of the thermostat boss. There is no path for the Bypass hose with the Factory Magnum A/C bracket.
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