E body bucket seat questions…..

Guys, bought these at a swap meet many years ago for my 73. Seller said they were for 71-72 cars but would fit a 73. Question is, time to order new seat covers, can i order covers for a 73 or do I need to order ones for a 71 or 72. Basic question , are the frames the same for 71,72,and 73s.....thanks.....Can t seem to post photo , must be too large.....

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Author: bandit 73