I'd say yes.. but I'm sure we'll have more than one response. I think there are subtle differences, but nothing major. convertible frame is boxed for support with no roof.. other than that.. I think your good for 64-67 A body frames
I think when this question was asked a while back one of the comments was the farthest back crossmember behind the bumper was different. I think as far as function it was said to be 100% though.
I know the 67 coil springs are unique at the bottom but the top likely works 64-67.
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1966 Strato Chief 2 door, 427 4 speed, 45,000 original miles
1966 Grande Parisienne, 396 1 of 23 factory air cars (now converted to a "factory" 4 speed)
65 and 66 frames share the same GM part numbers. You could also use a 64. You could use a 67 but would have to use 67 rear springs as the top rear spring perches are different on a 67.