?? Bleeding and adjusting brakes with power brake canister.

[8door]

Just installed a new master cylinder and new power brake canister.
Did a bench bleed on master before installing and cleaned all the lines
and installed new wheel cylinders.
Began the air bleeding lines and filling them with fluid. Starting with right rear
wheel my wife slowly pushed brake pedal while I opened and closed the bleed nut. Then moved to the left rear , after all air bubbles stopped there is not very much pedal.
I expect the pedal to be up and firm with just two rear wheels.
As this is is my first at bleeding a power brake system got other questions :
1.Do I need to start the engine and get vacuum to the canister while bleeding ?
2.Or can you feel some firmness in the pedal ?
3.How do I adjust the master cylinder push rod ?
Thanks guys
This is the one time I can direct my wife to do as I wish he he.