I credit alot of my research to this post by "cushjbc" on benzworld.org forum

https://www.benzworld.org/threads/he...pumps.3041049/

Vacuum Switch Schematic (1).pdf

Im including how I wired mine expect I used thicker cabling for power and ground for the 30 and 87 wires

f3fb74cf5291be47ab05be5f2daeb99d.png


If anyone does buy the PSF109S-81-330 Vacuum pressure switch
note that it uses the smaller blade connectors, I bought these 4.8mm female blade connectors and crushed them with pliers a bit to fit the 4.7mm terminal