Spring height school me!

Spring height is determined by the spring manufacturer to achieve the valve closed pressure value.
That is the height ( installed height ) you want to achieve through locators / shims and how deep you cut the seat when doing the valve job.
Picking up a lot of space by sinking the valve is a bad idea.....if you have to pick up a ton of height , you need to figure out a plan B.
Excessive shimming under the valve can be done to shorten the height , but try to do it with as few pieces as possible.........an .060 shim instead of two .030's etc.
Equalize the heights , then pick a spring that will work with the height you have to work with........there are a lot of spring options that have the same rates with installed heights from 1.75 to 2.0 ".