Grandpa, also found some installation instructions that might help:
These are exactly what you need if your existing RV gutter does not have spouts and rainwater drips down the siding like mine. However, it will require the use of a screwdriver, possibly a drill, and butyl tape (optional) and Dicor caulk to repair the molding. To install, the molding trim will have to pulled up to reveal the screws that secure the gutter rail/molding to the wall. Remove the screw so the gutter rail may be pulled up from the roof so the gutter spout may be slid in from behind. Position the gutter spout at an angle that will have the best water flow away from the RV. This product was twice as wide as the actual gutter width of my RV so I had to position them at a 45 degree angle to prevent backflow or overflow. Drill the screw back into the gutter rail and through the spout back. Butyl tape isn't a bad idea to place behind the spout and the screw hole for waterproofing, but that's up to you. Also, there may be gaps and cracks where the molding pulled away from the roof, so make sure to caulk Dicor lap sealant into these areas to prevent water damage to the roof and walls. Last, lay the molding trim back. In conclusion, this product is a perfect solution to divert rain water away from the RV, but the installation is not as quick and easy as the product description lets on.