New Engine, Hard starting, Likes Lots of Advance

Did you check to make sure the harmonic balancer "zero" mark is actually correct? When I was a kid I had a Pontiac that was the same as you described and I found that when the position was at TDC the harmonic balancer mark was no where near zero.

BTW: does it run right when you leave the timing advanced? When you check the timing you are doing so with the vacuum advance unhooked, correct?