Cold start issue

[BDC90]

Old Q-jet 1971. Runs good idles good starts when warm right away. Cannot get it to start cold without a tiny sprits of fast start. Carb rebuilt , settings double checked. There is some primary shaft play but it returns to 650 rpm when I let of the throttle. Is rebushing the shafts really gonna fix this? It doesn't seem like that little bit a vacuum leak would have that much negative affect with choke on during cold start. Anybody got any ideas? Accelerator pumps down both holes (4MV) , no hesitation when the throttle is blipped.