When I dismantled my truck I had a lower a deflector seal that was stapled onto the radiator side of the air deflector. Is this a necessary seal? LMC does not sell a repro one and I can't find that anyone else sells one.

 

I think you could slit a 1/4" hose and slip it over the edge.

 

Early ford store has them out of san dimas ca. 1948-1952 Ford Truck Radiator Grille Splash Pan to Radiator Seal
[7C-8348-A]$4.50

 

Yeah, they're available. My '49 has a replacement seal that I got sometime around 2012 but I do not remember where I got it.

 

Try Sacramento Vintage Ford. I bought one for my 51 there a couple of weeks ago. They have good online service or you can call them directly. They know their Fords.
Hope this helps
Dan