Here's a quick-how to on rekeying the Sears Craftsman tool chest wafer locks.
Note: Some of the newer locks have a locking lever that's rivited or soldered in place and there's no way that I know of to take them apart that will allow you to put them back together. They can still be ripped apart (I used a Dremel and vice grips) to harvest extra wafers and such, but that's about all. You need the kind of locks that can be reassembled to rekey them.
If you have a partial or complete too chest set (roll-away, intermediate chest and/or top chest) then all you need to do is buy the #965584 keyed lock set (for 26" tool chests), #965587 keyed lock set (for 40" chests) or the like from Sears and install them. Be sure to get the set that goes with your tool chest type as there are several types and each uses a different set of locks. This will solve the problem for most people. They're already keyed together. It's quick. It's easy.
On the other hand, if you have more than one set of tool chests or some other combinations (say, two or more intermediate chests) Sears doesn't provide a way to key them the same. You can't even order matched sets, I tried. But you can rekey them yourself pretty easilly. You'll still want the keyed lock set (mentioned above) and you'll want to install as many of those keyed locks as you can to start with. It's a lot easier to rekey one or two locks to match the others than to rekey all of your locks. Also, you'll need the spare locks you replace with the new ones to harvest a wider slection of spare wafers from.
To disassemble a lock you depress the retaining pin with a jewlers screw driver or the tip of a knife and push the plug forward, it'll just slide right out. The wafers on some older locks seem to just kind of fall out so be careful. The newer locks seem to hold the wafers in by the retaining tabs and you have to pull them out (straight up, gently but forcefully) with pliers or pry upwards with a jewlers screw driver or knife tip. Once the wafer is removed its spring is free to just fall out. Some springs do fall out and some need a little tapping to persuade them. Sometimes they change their minds without warning. I found that removing each spring with each wafer and then reinstalling them one at a time as needed helped me to keep track of them.
Most of the wafers, certainly the newer ones, have little numbers stamped across the bottom or on the srping tab. In theory you could take one of the keyed locks apart, jot down its numbers and then use those numbers to pick out identical wafers sets for the other locks. In practice that didn't work for me. I don't know if I read them wrong or if different batches from different times/sources give different meanings to the numbers or what. What worked best for me was sorting the wafers by their "size" and then test fitting with the key by educated trial and error. Often times once I found a match the same number would work in the same slot on other plugs, but not always.
Reassembly... With 20/20 hind sight reassembly is pretty obvious. Embaressingly it took me some trial and error hit upon it. Put the key in the lock, which aligns all the wafers. Then you only have to worry about the retaining pin. No fuss, no muss.
Note: You don't really NEED all 5 wafers (pins) in all of your locks. These locks aren't tough enough to keep out real thieves (who'll likely steal the whole tool box anyway). In some cases I only used 4 just so I had enough to go around.
The Sears wafer lock annotated, assembled and disassembled
Lock with key inserted some wafers too high, some wafers too low and one wafer just right
Top veiw of lock and wafers
Bottom view of lock and wafers