I rounded the bleeder screw - what now?

Hi,

I bled the brakes in my 2002 Alero yesterday, for what I plan is the
only time. I'd like to know the bleeding process I'll have to follow,
now that I have to replace one bleeder screw.

Two of the bleeder screws were rounded in the process. I used a flare
nut wrench specifically designed for softer fasteners.

One of these rounded screws was apparently not tight enough. I
discovered it was leaking. I capped off the bleeder screw with a small
plastic cap and hose clamp. Today I plan on buying new bleeder screws
and installing them.

I understand I'll have to re-bleed the wheel where I'm replacing the
screw.

1) Will I have to re-bleed all the wheels?

2) Will I have to bleed the master cylinder?

I'm not looking forward to this, but I have a Mity Vac and hopefully
that wil make things better.