I agree with everything Jerry said, but I never thought of it that way! I just focused on the nuisance aspect!
Another reason (also completely unnecessary) that I like to do the modification is that the timing covers differ for AD, TF and 60-62 trucks because of the engine mounts. The shape of the timing cover is exactly the same, the bottoms have different hole patterns because different style engine mounts were used. AD's have the square holes to accept a carriage bolt dropped from the top down, the TF's don't have any holes and the 60-62's have round holes. They can all be adapted to fit any model, but if a guy wants the correct timing cover to fit the engine mount for a particular year truck, or wants to remove the timing cover to adapt it to fit a particular year, this modification makes it an easier task because the pan doesn't have to be dropped.
Matt
