Hi guys I'm new here, and have just purchased a GU 2.8, I'm about to do the EGR and butterfly and thought whilst I'm doing that I'll clean the inlet manifold and intercooler, is there a certain type of degreaser to use, or any will be fine? how long should I let it soak for? is there such thing as it soaking too long? also if I remove the inlet manifold and clean that up, is the gasket re use-able?

thank you