Not sure this is referring to what you are asking... but I bypassed the entire hot water piping which is supposed to head to the front heater and then back to the engine bay.... right at the engine bay. Just connect both ends of it with a 6 inch or so silicon hose. It's kind of like a permanent heater bypass mod.
Highest temp was 105 DegC on start stop traffic. When car is moving, drops to 83 ~ 85 DegC.