Got a new mani and decat to fit but from the looks of it the exhaust manifold has not been removed like ever so it's been a bit of a bastard to get off, I have soaked them in WD over night tried it when it's warm, cold etc etc. What is the best way of freeing them without cracking the head? also how do people get the 2 central nuts and the two at the bottom? they seem awkward to get at!