I'm waiting for the rotors to show up so I have some time before I will want it back together, but I did the initial bleed and was able to get them to build pressure fairly easy using the traditional method and using a hand pump vacuum bleeder. I saw some people suggest to tie the lever pulled so I have it sitting that way for now. Will bleed them again later and probably again tomorrow and see what I get.
I thought about getting a syringe and filling the caliper that way before I put them together, but decided against it due to not knowing where exactly to find one that would work. If I can't get them bled I will probably just bench bleed them like @Dnyce suggested.
You can use the pump function on the vacuum to fill the calipers if you want, but I've never had to do that after caliper rebuilds, they will bleed just fine.
I've left the brakes applied(ziptie and weight) overnight on many bikes over many years too, and Always get a little more air out.