Thanks to lots of clues, I found out what Craftsman calls these tools:
Ratchet Speeder DiscsI realize they are made to pop on a ratchet so you can speed things up after the subject fastener is loose, but I was using my 1/4” drive ratchet speeder disc for another reason:
I put an aftermarket saddlebag rack on my 2007 KLR 650. Because of the rack, I can no longer get my #3 JIS screwdriver on the port side cover's rear-most mounting screw to get said screw started square and true:
As you can see, said screw is positioned down a narrow recess. To the right of the screw, you can see the luggage rack's port side rail (silver colored). Said side rail precludes the use of a screwdriver that is wide at that point (e.g. if a screwdriver's handle was there, it would not fit). Also, the black square tubing (seen in the foreground), part of the aftermarket saddlebag rack, will not let me get a straight shot at the screw using a long-shafted screwdriver.
While I have no trouble
loosening said screw (using a long-shafted #3 JIS screwdriver – it doesn't need to be absolutely square and true to loosen said screw), I was finding it impossible to get said screw
started using said screwdriver without threatening a cross-thread.
Clearly, I needed to find (or make) a screwdriver that had the needed dimensions.
Neither of these two screwdrivers worked:
The larger of the two stubby Phillips screwdrivers was too long (i.e. it hit the black tubing). The shorter of the two had a handle that was too large to fit into the recess.....and the shaft was otherwise too short to get the screw to its hole.
I tried a finger grip socket adapter:
But, as I had no Phillips bits of the proper length, this, too, was a non-starter.
So, I cobbled this together:
This is a #3 Phillips bit in a standard 1/4” bit driver, which is on the end of a very short 1/4” drive extension, with a 1/4” drive ratchet speeder disc, topped off by a 1/4” drive socket cap. It turned out to be exactly what the doctor ordered:
Thanks, everyone, for your help!