I have a 2008 Permagreen Magnum B2B spreader sprayer, bought used 2 years ago with 40 hours on it. I've only spread with it so far but want to start spraying. It's running 3600 RPM and I read where it shouldn't go over 3450, but the tach quit on me today. So help on that is accepted. Question is: How wide is your sprayer spraying? How many gallons per thousand square feet are you getting? When I drive it down the driveway spraying -- low gear, high gear sprayer nozzle -- it doesn't cover the drive very well. I'm concerned about getting adequate coverage / results. Thanks!