you are correct. there are 4 (in 72-L), one is at the very front behind the 1/4 window. the other three are distributed along the door weld you mentioned. The weather strip, whiskers, are also held by screws, very, very tiny screws. Some people use 3M double sided tape to fix the strips instead of screws. If you don't have the screws, you might try specialty woodworking supply houses for their miniature trim screws.
Hope that helps.
Glenn
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