From what I remember (going back to the 90's when I was in the scouts) the clusters were certified by using a tuning fork (scout leader/police lt. said this was how it was done) before the digital clusters. Not sure how they do it nowadays, but the speed will be perfectly fine, unless there is a major gear/wheel/tire change. Others can chime in with more specifics.
"Never Will I Leave You; Never Will I Forsake You." - Hebrews 13:5
'95 Caprice 9c1 ~ Former NYSP Cruiser