As most of you know, James Kolar suggests toy train track with the center pin removed as the source of the "stun gun" marks. In the book it is called O gauge, but what is pictured is IMO actually Lionel O27 gauge. Not really an issue because the distance between the pins would be similar. I can certainly attest to the fact that the pins do come out with normal use. However what the train talk really reminds me of is the fact that many O and O27 steam engines have a curvature to the roof of the cab. So looking at it from behind, there is often a curved roof protruding to the rear. Also, these die cast locomotives can have considerable heft, imo enough to cause the damage to JB's skull. There are however two issues - 1. I'm not sure that there was a model with a cab as narrow as 1 3/4", without going down to a smaller gauge, where the heft and potential for damage drop considerably, and 2. The damage to the skull appears concentric to me, and I can't say how the toy engine as the bludgeon could provide that. So, the question for me becomes, were the toy trains and accessories cataloged with any specificity? I would suspect that if a locomotive was the weapon, and provided that the R's knew it was the weapon, then it likely went the way of the tape, rope, and practice notes. But this stuff often comes in sets, so any info of what pieces were there could be helpful.