Please help a stupid beaver with step by step instructions.

TL:DR Dumb beaver needs step by step instructions to create SR Switch out of the Automation structures available.

Goal: Setup my Mine so that when scrap falls below 500 it deploys workers to rebuild the deficit.

Hello. I am a dumb beaver. My birch-brain does not understand specifically what to place, what to click, and what to attach to make a "Set-Reset" switch. I know it involves relays. I am sorry, I do not understand logic circuits well or how to string them together to make this SR Switch.

I would be supremely grateful If some very kind worker beaver could explain what specific logic structures to place and how to have them interact in such a way that creates said SR Switch.