FYI it's a [JST S4B-EH](https://www.digikey.com/en/products/detail/jst-sales-america-inc/S4B-EH/926535) Although currently OOS on Digikey, $0.22.   FYI: There's no tab on the earlier chassis' to keep the smaller boards like Model-H in place, had to resort to sticky back foam.