Plumbing and Piping - wtr pressure 2 hi

My well pump is pressurizing my holding tank up to 92 pounds. I always thought 50 was max. The pressure relief valve is blowing water onto the basement floor whenever the pump runs until pressure drops. On the control, there are 2 posts with a nut a spring on each. There is a tall post and a shorter post. Which one should I adjust? And which way do I thread the nut: down to increase pressure on the spring or up to decrease the pressure on the spring?

I'd like to get the pressure down to 50psi or less.

Thanks much!

First, check the air pressure in the pressure tank, if it's an air bladder type, with a tire pressure gauge at the air valve near the top.
It should be about 30 psi, or about 2 psi below your normal pump cut-on pressure. It doesn't have to be exact, but the cut-on and cut-off should be about 20 psi apart.
Sounds like the bladder has sprung a leak, and is not creating enough back pressure to make the pump cut-off with the pressure switch.
If the bladder won't hold the minimum cut-on pressure while the water is running, replace the pressure tank.
The pressure switch also could be the problem, if it appears burnt or worn.
The taller spring-loaded nut adjusts the cut-on pressure, and the smaller adjusts the cut-off pressure. Turn them down to increase pressure, and up to decrease pressure.
Let us know what you find.
Good Luck!