Some years back there was an issue with our Sable with the engine making a loud tapping noise while running smoothly. Thread is here in the archives. Well never did find it despite having it apart twice. Heads checked, valves checked, pushrods checked, lifters checked, valve covers no marks, pistons no marks. I've been toying with the idea of getting a rebuilt short block and then transfer everything else over. Since the car is in the garage there isn't a way to get it high enough so I thought of stripping it down, again, then removing the short block from the top like other engines once disconnected. Unless I am missing something this would seem doable?