Valve spring installed height

Ok folks, I just picked up a set of Stealth heads from 440 source. My first go around with aluminum heads. I’m preparing to install my springs and they call for 1.90” +/- .020 installed height. After measuring one head I’m getting variances from 1.860”-1.878” Now by my calculations they all are tight and should be cut. So I’m thinking I’ll get the cutter/arbor and a pack of shims and do it myself. I’m not one to back down to a challenge and learn some new skills. Looking for some helpful input/advice as I move forward. Thanks