440 Help Needed

OP how did you verify top dead center?

With a piston stop. On the number one piston I rotated the piston up until it hit the piston stop. I marked the damper. I then reverse the rotation of the crank and marked the damper when the piston again hit the piston. My timing mark was exactly in the center of those two lines.

compression with that piston falls between 10:1 and 9.5:1 depending on head cc.

Well good to know... I do not know head cc. I do know the heads and block were decked, however I do not know how much of those components were machined, nor do I know the casting numbers of the head off the top of my head.