My 93 4-door had a 10-bolt with ABS.  When i did my ARB, i had a spare matching 3rd (with ABS) and put the locker into the 3rd member, then put the whole chunk into my rear end.  The ARB air locker doesn't utilize the ABS ring.  When i put the 3rd back in, i hooked the plug back in, even though i knew it wouldn't do anything, but it does seem to complete the circuit and the dash brake light doesn't come on.

The difference between a 10 bolt and a 12 bolt is the amount of holes that the ring gear uses to bolt itself to the diff case, not the number of bolts/studs the 3rd member uses to attach to the housing.  The ARB's have 2 different part numbers, which are basically exactly the same thing, except the cases and flange caps have 10 or 12 bolts.  If you have a 10 bolt ARB and want to put it in with a 12-bolt ring gear (if you switched gears or something), you'd just need to buy a new air locker case and flange cap for the 12 bolt and swap all the internals.

The other trick you can do to trick out the ABS units is use the 3rd member housing you're pulling out of your rig and install the 10 bolt internals and new gearing into that so you can plug that cable back in (not that it does anything).