(Plymouth, MN)  —  Plymouth Police made a breakthrough in the murder investigation of a youth baseball coach from more than a month ago on Highway 169.  Court records indicate that investigators found an SUV that may be connected to the shooting.  Jay Boughton was shot and killed while traveling on the highway just south of County Road Nine on July 6th after what police believe was an altercation with another driver.  Police say surveillance images from that night are blurry, but dozens-of-tips helped them track down the vehicle in question.  No suspect has been arrested at this time.