Think that's what the small hose off the booster, that's blocked off, is probly for?
No, that one at the booster is for speed control. It’s too large for that other line.
here is a photo of a 62 Chrysler with the hoses. Fingers to the small one, the larger one right there is to the PB. The lettered hose crossing diagonally is from rear of carb to PCV.
Glad I could help you out! it’s easy to do with the good photos you are showing of your car. We got @HWYCRZR sorted out also.