The Lions began what could be a major overhaul of their offensive line today, informing right guard Stephen Peterman of his release, according to a person familiar with the decision. Peterman, 31, started every game at right guard for the Lions the last three years and has been a fixture on the line since 2007. But Lions general manager Martin Mayhew said the team allowed too much interior pressure this year, which contributed to Matthew Stafford’s struggles at quarterback. Peterman ranked 14th in Pro Football Focus’ offensive-line rankings at right guard, and the Lions were third in PFF’s pass-block rankings as a unit, allowing just 29 sacks in an NFL-record 740 pass attempts. With significant salary-cap problems, the Lions have targeted the offensive line as an area they can get younger and cheaper for next year.