1950 F1 with Merc flathead

[Flathead Noob]

I am new to the world of flatheads and all old Fords, for that matter. Recently bought a 1950 F1 from the original owners granddaughter. At first glance, it looks like a well worn, all original farm truck, but after wiping off some crud I find the cylinder head is an 8CM Mercury.


Like I said, I'm new to this world. Did F1's, for whatever reason come from the factory with a Merc engine? Or the simplest explanation of just being swapped in at some point?


Thanks for your time!