200 hs skip timer

The new LL IV has a computer that shows distance, mil thickness, etc etc. How about a skip timer option, or just a counter that when set will flash a red or green light like stop and go. The operator then would actuate the gun on green and stop on red. I just striped a bunch of road and have a 5 1/2 mile project coming up. This would be a great help. Even though it is a fraction of the jobs I do it goes along with the glass bead dispenser. Its nice to have when needed.