How exactly do I take the heads off of my m117? Obviously the bolts need to come out, but what do I do with the timing chain to release it from the sprockets on both sides? Does it need to come out completely.....or should I just pull it through so that one end hangs out each side of the engine? Thanks in advance from a total newb

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1999 C43 AMG ~~~ 744 on black, mostly stock
1991 190e 2.6 ~~~ m117 5.6 project car