Supposed to be a bolt in, some guys say yes . Others say it’s a mix of both years . either way yes you can
It's just me, but I would never put '40 headlights on a '37 or for that matter, a '39. Both of those years have such great and distinctive headlights, it just doesn't feel right to change them to '40's. Guess that really didn't answer your question.........Don.
I like the looks of the stock headlights, but back in the day several companies made sealed beam conversion kits with headlight doors that looked very similar to the '40 Ford headlight doors. Some were painted (like a '40 Standard car and '40-'41 pickup) and some were chromed like a '40 Deluxe and Merc.
I recall them on a late 40s early 50s Dry Lakes 37 Coupe that was a participant and although a rare dare I say Non Traditional through being a rarely done mod it was and looked pretty cool in my opinion... Sorry it was a 36... https://www.jalopyjournal.com/forum/threads/old-hot-rods-photos.1038554/page-5#post-11800117 Again what your suggesting is a rare mod that would be period correct but not a Traditional expression in Hotrod/Custom Credit to Photographer, Owner
Ok, I went with the original 37 ford headlights. My grandson and I did install sealed beams by modifying the reflector bracket.
I don't think they are a bolt-in, like they are on a 39 deluxe. If you put 39 Deluxe and 37-38 headlights side by side, you'll notice the 39 deluxe is wider, which also means the hole in the fender for a 40 is wider, which means the hole in the fender is narrower on a 37-38, and not quite the same shape. Look at a 37-38 bezel, they come to a point at the bottom where the 39 deluxe is more round. In summary, find an old aftermarket sealed bean conversion for a 37-38 or use the stock headlights with a Vintique halogen conversion kit. On a purely aesthetic level, the sealed beam conversion kits they had back in the day are ugly.