'69 Dart fuel filler neck lip same as '67 Cuda?

Hi,
I am adding a '67 Barracuda flip top fuel door onto a '69 Dart resto/rod. Can someone confirm that the lip of the fuel tank neck filler are identical geometry on the two vehicles?. The reason I ask is, I also want to use an original Cuda locking cap (more of a locking 'plug' really, original Chrysler option part for under the Cuda fuel door). And before I spend the $150 that those original locks are going for nowadays, I want to confirm it will fit the '69 Dart neck.
Thanks much!