(Seattle, WA) -- Boeing is moving forward with plans to build its 777X jetliner in the Seattle area. A crucial labor contract was narrowly approved by Boeing's machinists with a vote of 51 percent to 49 percent Friday night. However, approval of the contract means workers will concede some pension and healthcare benefits. Members approved an eight-year extension that the union said provided a billion dollars in additional benefits, but which will stop pension contributions in 2016. Had the workers rejected the offer, Boeing said it was ready to work on the jetliner elsewhere.