The video skipped over how to get the shaft off the spot light head. I've done this a long time ago. Apparently, you remove a bolt or screw through the head- and remove a small screw from the top - one of mine has a regular head screw and one has a Phillips. But even after removing these, I can't get the head off. I need to get the head off only because someone put the "ring" on the shaft permanently and I can't insert the unit from the outside-in, as required. This presenter noticed the damage to the unit by a prior user. On mine, there is no head to the screw holding that little ring in place. It's sunk a bit and flat. I guess I'll have to blast. Back to trying to force some opening in the base of the head where it looks like it should separate. Any thoughts? Thanks in advance!