Before we can do the final hookup of the KD electromagnetic uncouplers we first have to provide a source of DC power. In this case we'll need both 12VDC and 16VDC to power the control circuit and electromagnetic uncoupler, respectively. When selecting parts keep in mind that as of the end of August 2023 All Elecronics will be going out of business but Quick Splices and T-taps are available from Amazon and eBay. Here is a short parts list.
The Quick Splice #7200 16-14AWG connector is an All Electronics part so act fast or look for similar ones on eBay.
The buck boards are readily available on eBay, search for DC buck board voltage dropper, etc. The vendors change so regularly it would be fruitless for me to list one.