I'm actually using the same ports as you are for the heater. The plugged hole in the front was 1/4" NPT and I drilled and tapped it to 3/8" NPT. I plugged the heater port from the inside behind the water pump. Only because I already had the timing cover and damper re-installed. I couldn't come up with a good way to run the hoses out the back since my heater hoses go through a bulkhead on the inner fender close to the radiator support. Keeping them up front will make them run about how my LA hoses are run currently. Those supercharger fitting are cool!
This is the same thermostat housing I have and it did supply water to the oil cooler. My engine is an 06 from a low mileage crashed pursuit car. I'm not using the oil cooler, so I'll likely try to find one without it, or cut it off and weld the hole up.
