When I said "take a picture of the wiring connectors," that was just for your own reference for when you swap out the gauges. Also, only change one gauge at a time if possible. That'll make your life a lot easier.
You'll need to repair your dash bezel or replace it to fill some of those empty holes. I can see that the bezel around the gauges has cracked/broken and fallen in.
Those look like Faria gauges. Take a picture of the wiring connections on the back.
I've attached some pictures of the work I had...
