The next two numbers after ms is month of production. War production board would not allow new models so they ran with '42 model of ms. '42 is 1-12 months '43 is 13-24 '44 is 25-36 and '45 is 37-48. It should have a bare weld at base of "a" pillar next to windshield, leather gas fill grommet and painted stainless trim on side of hood.
Rh