The Pentagon's top acquisition executive has approved a plan that could expand the number of armored truck builders producing Mine Resistant Ambush Protected vehicles even as senior military officials are poised to reduce the total size of the MRAP acquisition objective, according to sources familiar with internal Defense Department deliberations. John Young, under secretary of defense for acquisition, technology and logistics, on Dec. 14 approved a plan to award one or two vendors contracts for a half-dozen prototype MRAP II...