To R&R the brake booster is a relatively easy job. If not for the pita to reach the nuts it would be a 2...but the tight quarters raise it to a 4.
Tools required are:
12mm wrench
Ratchet
Deep 12mm socket
16mm wrench
Needle nose pliers
Light source

First remove the clamp and vacuum hose from the booster.
Next remove two 12mm nuts that hold the brake resivoir to the boooster.
Next remove the hard lines from the clips and move them as needed to remove the resivoir and move it out of the way.
Next remove the four 12mm nuts near the brake pedal using a wrench or deep socket. Having small hands and being flexable helps a lot!
Next use the needle nose to remove the "spring type" cotter pin from the brake pedal/shaft bracket.
Remove the connecter pin.
Now you need to wiggle, twist, pull the booster out from the tangled mess of hard lines and wireing harness's. Up and to the drivers side worked best for me.
Once the old booster is out transfer the shaft bracket to the new booster. I counted the threads on the old shaft before removing and replicated it on the new shaft so the adjustment would ne correct.
Now transfer the front and rear spacers to the new booster. The rear spacer has a foam type gasket that I was able to reuse. The front spacer has paper type gaskets that were not reusable due to age. I used a liquid gasket.
Next repeat steps in reverse to install new booster.
Complete job took me just under 2 hours from start to finish.
Be sure to test brakes in a safe area afterwards.
Hope this helps!