your diy is awesome! but i might have a correction. You donīt need the torx 50 socket, the belt tensioner have a hex shaped thing to put a 15mm hex socket on it and release the pressure to take the belt apart. Like in the AC belt, you donīt even need to pop off the little black cover from the belt tensioners.
Also, i might use part of your diy to write another about how to change the oil filter support gasket, which is known to fail and cause an oil leak.