I created my own adjustable pushrod. From an old OEM pushrod, I cut out 1.75" from of the middle leaving two 3" end sections. Next I got a 6" piece of 3/16" all thread and use two nuts to adjust the overall length.
Are you saying use the solid lifter to measure then factor the delta in pushrod height when converting to a hydraulic lifter? I do have a 6" digital caliper capable (supposedly) of .001" measurements.