My way is not only faster then most traditional ways, but its also makes the trailing arm bushing come out without much resistance.
Things you will need:
Bigger C-clamp or PREFERABLY a vise
KY lube (not required, but if you have it I recommend using it)
First Cut off the head off each of the 4 trailing arm bushings:
To push the new bushing in again follow the illustration. Although not required, especially if you are using a strong vise; lube the outside of the bushing and the inside of the trailing arm hole, it makes it easier if you are using a c-clamp.