Replacing 68 Executive Inspection Car Reversing Knob

Well, never got an answer.  Google and youtube had nothing, nor did old posts on OGR.  So, I started carefully drilling a hole in the old knob from underneath, next to the metal holder it attaches to.  Since the drill would just go through the top of the old knob, I figured I could do it with low risk to the body.  I kept on drilling holes in the old knob until it finally loosened from the holder.

Putting the new knob in the holder was actually hard as well.  I put some grease in the slot of the hole of the knob, and actually also made the hole in the knob just a bit wider.  With the grease and the wider hole, it still took more pressure than I like to use to get the holder into the knob, but I finally did.

Update; The metal holder has little nibs to stick into the knob so it doesn't come loose.  I imagine that carefully heating the part of the metal holder that goes into the knob would slightly melt the sides of the hole in the knob allowing for easier insertion.  That would have to be done by the next guy!

I thought I might put in some more info about Lionel's executive inspection car for posterity's sake.  Referring to the picture, this is the new Lionel e-unit I got from a vendor on the bay.  Note the plastic looking part inside the red circle.  It is designed to fit securely against the metal frame, but it does not.  It always seemed to be dangling, as shown in the picture, shortly after I snapped it into its location.  After installing the new unit I was having problems with getting it to work consistently.  Looking at the old e-unit I removed, that plastic part was fiber board (I think) and it was firmly attached to the frame.  I used some super glue to attach the plastic part on the new unit to the metal frame, and the problem went away.  I reported this to the vendor, and they said that part is exactly how Lionel ships them.