It's not Matt Light but the Chiefs did pick up a former New England offensive tackle -- Steve Maneri. The 6'6", 290 pound offensive tackle comes out of Temple, where he played tight end (and was a team captain).
Maneri was waived by the Patriots and hit the waiver wire, which means that every team, in draft order, had a shot at claiming him (and his contract). The highest bid wins and that was the Chiefs.
The Chiefs had just seven offensive linemen which was one less than they'd normally carry and that included three offensive tackles -- Brandon Albert, Jared Gaither and Barry Richardson -- and now Maneri becomes the fourth offensive tackle. He's had a little bit of experience as a swing tackle so he can play on both sides.
To make room for Maneri, the Chiefs released TE Anthony Becht who was just signed earlier this month. It's very possible this marks the end of Becht's career as he was transitioning to a role with the media before the Chiefs called.