that is brutal. the 19x20 should have pretty well no travel at all before biting (it's got the most plunger travel per lever travel, basically the least leverage, but tightest lever)
my setup with a 19x18 has maybe 1/4" of free travel before it's firm. yours should be even tighter than that.
try bleeding at the master first, once the master is clear bleed at the calipers.
leave it overnight, then bleed at the master again. the highest point in the system is the bleed nipple, so any air will collect there.