I went through this two years ago on a tail dragger I had just purchased. Those wheel locks SUCK.
I was terrified to use the hole saw method. But after trying all other methods recommended (including molding the pin pattern in clay and then welding up my own key) per the majority over at Pelican, the hole saw really was the only way. One thing to note - do
not take off all of the other nuts. This puts more pressure on the lock.
Tighten all of the other nuts as much as you can to relieve pressure on the lock. Buy two or three different brands of hole saws, as the various tooth designs will impact how they fit over the stud. These locks drill very easily - so go slow.
I also bought a die to chase the threads on the stud afterwards - I got lucky and my local Sears had the correct one.
First one took about 45 minutes as I was so terrified. Second one took not even 10 minutes start to finish.
I fully agree that the other lugs should be left tight.
If the others are removed all clamping force is on the single fastener that you are attempting to loosen.
The company that made these locks is long gone - so there is no way to get a key. In my attempts to find a key that would work, I was informed by someone in the know over at pelican that there were thousands of combinations. If you have these on your car, get them off and throw them away.
I fully agree that the other lugs should be left tight.
If the others are loosened all clamping force is on the single fastener that you are attempting to remove.