Originally Posted by auchencrow

The PArk Tool brake wrench is a big help on some of them - but it will not fit some calipers due to tight clearances.
In those cases you can try budging the the pivot by whacking down on the spring with a drift - this often works if you can calibrate your arm well enough.
There are also a variety of third hand tools available (if a second person isn't) - This definitely makes centering a caliper much easier.
With the right method and tools, it is possible to center almost any side-pull caliper.

PS +1 to Michael Angelo's advice on the import of getting the brake housing to just kiss the adjuster w/o pushing or pulling.
Also I want to try his star washer idea for myself.