Yup. Not hard at all, just takes some patience and a lot of staples.
I have a late car, but instead of trying to recreate the late version where the pressboard is formed at the top to replicate the metal strip (if I recall correctly), I bought the metal top strips from someone that were from an early car and just cut out a pattern using pressboard from home depot and vinyl from the fabric store that matched the seat bolsters. I could've gone with the original basket weave material, but I hate that stuff and thought the door cards looked better matching the seat material.
Don't forget the vapor barrier.
I didn't take pictures of how the 'tuck' at the top strip is done, but there's a thread on the site somewhere showing detailed pictures of how it's done.
I'm happy with how mine turned out.
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