Scoot the mound up a few feet.
Then get one of those radar guns that have two speeds. First reading is actual speed, second is what it would be if throwing from 60'6".
It works in the LL World Series, have you seen how many kids throw 90+?
If you move the mound far enough up I could throw 90+!
"God knows I gave my best in baseball at all times and no man on earth can truthfully judge me otherwise."...Joe Jackson