DumbAss references the jack. You want the corresponding plug. Something in the 5792-12116 family should work. You need 5792-12116-05. Marco has -06. You can cut it down. You will also need the wire punchdown tool for .100 to push the wire into the connector.

The wires run through the connector. They do not terminate at the connector. Therefore you want the "through" version of the connector. If you get the "end" version, you should be able to cut the little end walls out.

It looks like Marco has only "end" versions in .100. Only listing mt/end rather than the mt/thru version. Williams probably had a different 5792-XXXXX part number for the "through" plugs. What Marco has is close.

As noted by @dangerterror, the connector is tiny.

https://www.marcospecialties.com/pinball-parts/5792-12116-06