[Adam]

I believe the last Cadillac to offer a manual transmission would have been a 52 or 53. I'm nearly certain they all had autos by 55.

I think the last full size Chevy (Biscayne - Bel Air - Impala - Caprice) to have a manual was probably around 73, certainly the last of the manuals would have been in the 71-74 era (and this probably would have been some rare stripped down 3-speed column shift model, I don't think they put 4-speeds in after 1970 or maybe even 69 - I've never seen one with a 4-speed newer than 68). I don't think they made any 75-76s with manuals at all.

Full size Buicks only offered a 4-speed from 63-65, but the 3-speed manual continued as a rare option into the early 70s.

Oldsmobile seems to have made a few full size 4-speed cars in 65-66, and also continues the 3 on the tree as a rare option into the early 70s.

Pontiac offered 4-speeds in their big cars as early as 1960, but probably discontinued them in '68 (I've never even seen a picture of one newer than 68 with the 4-speed). I think here also the column shift 3-speed continued as a rare option until at least '71.

If I could go back in time and special order any car I wanted, I'd be a 60 Buick Invicta 2 door hardtop with the 401 nailhead and a 3-on the tree (I think the only 60 Buicks they really made with the 3-speed were base model Le Sabres with the 364 - 2 barrel engine). Actually, I'd love to find any of the 59-60 GM full size cars, especially one with the 3-speed.