Hesitation and stalling

A little background, converted my 76 Cordoba 400, from lean burn to electronic ignition. Swapped out the lean burn carb for a 75 440 carb.

The conversion went well, the car starts right up, with no gas peddle pumping necessary. I set the timing and adjusted the carb, however, I am now getting hesitation and stalling when I accelerate.

Any thoughts on what may be going on?

Oh yeah, one other thing, after the initial start up, if I shut the engine down, it's very difficult to restart. Though if I wait about 5 minutes, it starts up! Again, any help is appreciated.