The lowest paid U.S. factory workers at Fiat Chrysler Automobiles NV (FCHA.MI) (FCAU.N) would get the biggest raises and the most generous profit sharing checks under a new four-year labor contract, according to details of the proposed agreement released on Friday. United Auto Workers union leaders are meeting Friday to start the drive to win ratification of the contract from 40,000 UAW workers at Fiat Chrysler. The current contract allows for a gap of more than $12 per hour between the lowest- and highest-paid assembly line workers.