Sorry if I posted this in the wrong section, I figured the performance section would have the most knowledge. I have a 2004 truck with the 4.7, after the infamous head gasket failure I just got the engine back together with new pistons, heads re-worked, etc. and am ready to put the accessories on and fire it up. I already searched for over an hour to find out which way to clock the "jiggle" valve on the thermostat. I don't remember how the factory one was orientated. The new one does have the rubber tab that indicates it in the housing but the valve it at approx 1:30. I've read where it should be 12:00, 6:00 and other locations. I believe you can spin the gasket with the rubber tab and indicate it wherever you want. I know how to bleed the system but I also know how easy these overheat. Any ideas about how to position the thermostat? Or does it really matter this much? I just want to make sure since I have more money in this than the truck is prob worth, ha. Thanks.