Hey guys, before I do this I want to make sure I am doing my math right. I need to drop 1" "real life". At a 2% grade I calc. that would be 600' scale or 3.75" "real life". Or at a 1 1/2% grade I calc. that to be 800' scale or 5' "real". Is there a easy formula for this or am I correct in the way I am figuring this? Thanks................