Shell casings collected after the chase matched casings found in Clements' home, according to a Texas police search warrant affidavit obtained by ABC News.
Authorities said there is no clear motive for the Texas shootout, but they believed the Cadillac was pulled over as part of a drug stop. They were looking into Ebel's alleged affiliation with the prison gang 211 Crew to help explain why he was in Texas.
Ebel, who had the word "hopeless" tattooed on his body and was known to sign his name, "Evil Evan," died Friday of wounds.
Texas authorities said evidence found in the suspect's car -- including a Domino's pizza uniform jacket and a cardboard pizza box -- may also link him to the unsolved murder of Nathan Leon, 27, who was killed delivering pizza near Golden, Colo., last Sunday.
Friends of Ebel, who grew up in Wheat Ridge, Colo., told ABC News that he had been depressed and on edge for years. He had been in prison on an assortment of assault, robbery and menacing charges dating back to 2005, according to jail records.
"He was depressed a lot," Ryan Arici, a friend of Ebel's from Wheat Ridge, told ABC News. "And he was a dark person. His walls were painted black and his windows were blacked out."
ABC News' Colleen Curry and Clayton Sandell contributed to this report