gpw identification question

[futureuncertain]

I am parting out an april 1942 gpw here in Houston Tx. I have found a number of F marked parts and a few that are not (motor is mb). I can't find an f on the grill although I have found them on the headlight parts and bolts. Would someone tell me where to find the f on the grill? What about the axles and springs? It would help me sell if I could point it out. Thanks

I also have an oil filter (case/housing) that is marked "military standard filter" on the lid. Is that original ford or mb?