An alternate to all the above mentioned regarding returning to Zero...
On a rifle I dedicated to long range shooting, I shimmed the rear scope mount so that I could maximize the elevation adjustment. The side benefit was that my standard Zero is only 10 clicks from bottomed out. To return I simply bottom it out and then click up 10 every time. Nothing else to be remembered. Windage is just a few clicks either way usually, and for that I just marked an alignment dot on the edge of the adjustment knob base.
"Why is is called Common Sense when it seems so few actually possess it?"
Guns only have two enemies: Rust and Politicians.