The Cowboys have agreed to terms with safety C.J. Spillman, according to sources. Spillman was released by the 49ers, the Cowboys’ opponent on opening day.Dallas will have to make a roster move to get Spillman on the 53-player roster. Rookie safety Ahmad Dixon could be the player released as the Cowboys won’t carry six safeties.Spillman played 59 games for the 49ers the past four seasons after beginning his career with the Chargers, where he played for Cowboys special teams coach Rich Bisaccia. He has 73 career tackles on defense but is a core special teams player, having led the 49ers with 19 last season.Spillman was set to make $1.25 million in base salary with the 49ers and had a salary-cap number of $1.56 million.