I have a 1970 dodge dart swinger with a 225 and a single barrel holly carb, auto. I am just starting out working on/ restoring it my self and I need advice on a couple different problems.

Speedo; It has been working just fine until the other day. The speedo started jumping about 10-15 mph back and forth and making a whining noise at 35mph and up. i hit the dash and it helped a couple of times. Could this be because of the cold? Have heard rumors from other non mopar owners about this but I wanted to check with you all. . .

Stalling; She runs like a dream until I shut it off once and go to start it back up and give it gas, then it die's at low speeds and typically when I am turning. After that it'll die around random turns and started doing it in reverse recently (which it had never done before) I can give it a little more gas when I feel it starting to lug down, this only helps some of the times. It's only getting worse, not a consistent problem. I know I have routing issue's with my vacuum lines, could this be causing it to die at these specific times though?

Thanks!