Jimmi,

The oil pressure switch is threaded and screws into the T-fitting that screws into the block.

The T-fitting has one male end (into the block) and two female ends (one for the pressure switch and one for oil line to oil filter).

Here is an oil pressure switch that works on my electric chokes:
https://www.napaonline.com/Catalog/CatalogItemDetail.aspx?A=MPEOP6626SB_0213427398&An=0