If you get a water pump and thermostat housing for a big truck 261 it will have extra heater taps on both the thermostat and water pump housings. Also the bypass thermostat will get hot water to the manifold sooner if you hook it up right.
Or, just drill and tap the pump and water neck you have for 1/4 NPT fittings and run small lines to the intake. You don't need very much flow.
