Joe, Thanks for your reply--I was 99% sure they were 2.5in front and rear, but needed confirmation. Reason being I purchased drums from a well known parts supplier,shipped them to New Zealand, and found they were only 2.0in. I have been in contact with them and in 2 emails from them they keep saying Pronto BD8839 drums fit rear 64 Buick sportwagon. And they are still listed in their catalog. Seeing they were said to fit rear I assumed they would fit front as well, so I bought 4!!!! Hopefully I will get a refund even though it is outside their 30 day return policy, and then purchase 4 correct ones, which I think are AC DELCO 18B452. Regards and thanks, Bruce. PS I have 2 Sportwagons and a number of other BUICKS , DeSOTO etc.