Needs more initial, 33 degrees total is in the range, small blocks typically like 34 but experiment some.

I'd run 15-20 initial. You can do it the easy way and hook the vacuum advance to manifold vacuum if you're only concerned with increasing idle quality and not performance, or just as a temporary solution. You may end up with some other undesirable symptoms depending on the rest of the setup though, but probably not. You will just be losing some off idle performance.