Most of the traped air is probably still in the MC, but bleeding the system again is prudent because you could have introduces air into those lines.

I bleed the MC in place.....

It needs a closed circuit of lines coming off the MC and allowing fluid to be pumped right back into the resevoir bottle.

I keep a few short lengths of brake old brake line with fitting around for this purpose. Simply fit these in place of the lines to the brake circuits. Bend these over so they will stay submerged in the fluid bottle. Work the MC so that the flid pumps right back on top of itself.

You'll have to pump the brake pedal for this. Make sure you don't push it all the way to the floor, as wisdom has it that this can damage the MC seals (and why many use power bleeder devices for bleeding the system)

Also, clean these pieces of brake line to remove all traces of dirt, undercoating, etc. Orhterwise, the brake fluid will dissolve it and get into the resevoir, MC, Circuits.

(Gee, maybe that's my problem. See: "No rear brakes" above)

Finish off be bleeding the entire system again. This should help a lot.

BTW, if you changed out brake calipers, it is not unusual to need 2-3 bleedings in order to get a firm pedal.
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'Can't understand why people abort Volvos, either'