Ok so I'm working on a 96 Toyota 4runner v6 and it was having a over heating issue the heads were previously worked on by a shop but they got shut down the truck over heats really fast the radiator fan clutch water pump thermo stat everything was replaced i though maybe the shop put the wrong headgaskets so i removed the heads and it looked like a few water jackets were blocked and there was build up on the v jackets on the head gaskets im taking in the heads tomorrow for pressure testing, went to autozone to order new head gaskets and they looked almost similar but with different water jacket holes could this be the reason for over heating? Any info would help