Welcome to CHR! You mention a remote booster, which I assume is one that mounts in the trunk with a vacuum line running to it, and your MC feeds the remote booster, which then feeds the front & rear brakes, right? Something like this? - https://techtalk.mpbrakes.com/booste...vacuum-booster

Did you pipe your new MC to the remote booster or not? From that link, it appears that you need a dual diaphragm booster for a disc/jdisc setup. Did you change the remote booster, or are you abandoning the power brake part and piping straight from your new MC to the calipers?

You say that it appears all the air is out of the system. What method are you using for bleeding?