Years ago I put a seat out of a 60's Falcon 4 door wagon in my 49 F-1.... Worked very well.... Might fit your 41... If I remember right I used 3in. channel to raise the seat up to a good height.... LynnW
Depends on you - the Glide as you can see has a thin back so most people will fit. If you are a beanpole you may get away with swapping something from a 60s 4 door. One of these would leave 4" on each side - https://bulletproofoff-road.com/i-3...pice-rear-no-drilling-installation-41317.html Take a look at minivan rear seats they are narrower since the fit between the wheelwells.
I gave a friend a bench from an 80's S10 for his '47 Ford P-up cab. He stripped the upholstery off it, narrowed the seat frame at the front only, cut the foam to match, then had someone stitch up a new cover. Looks great, fits great.
When I had my '40 Ford big truck I used a seat from a Chrysler mini van. Think it was the second row but might have been the 3rd row. Fit ok but not all that comfortable. The stock seat in my '39 was OK but I finally bit the bullet and sprung for a Glide. Bought it at LARS and got the show discount. Not cheap but no shipping since they are just down the freeway. If you do go that route, my upholstery guy wanted to use his own foam not Glide's. Came out really nice. IMO
Build one from scratch. Plywood and shaped foam covered by some good quality vinyl or leather. Work with the upholstery shop to fit your contour. I have a seat like that in the deuce pickup and it's very comfortable. Also cheaper.
And that is the key on these truck seats, thin backs. We cut the foam down quite a bit to achieve a skinny seat back, left he bottom foam full for comfort.