How is Dad operating the trains. Traditional, (transformer handle) or command(using remotes)?
What are you trying to accomplish by the changes?
The pins in the center rail will separate the track in between two of them from the power of the rest of the track.
The pins for a switch, like that of K-line in the photo, are for the outside rails to operate the switch control rails for non- derail action. See instruction sheet for correct placement. I only have Lionel instructions.
The cross jumper wire should be soldered to the tabs where I drew the red line. The cut separates all four center rails in two still and two disconnected. The jumper wire connect the two separated tabs. This separate power of N-S and E-W to enable to separate transformers or handles to control track that crosses.
