is this a locknut over split shaft adjustment? Sears has hollow-shaft nutdrivers on the rack... drill through the handle, get a long-blade screwdriver, should fill the bill. might need to use a "lineman's bit", but they should have those also.
used to be standard Xcelite parts for this, but availiability is substantially lacking from what it was in the 60s and 70s.
Thanks for the lead. I've modified several Xcelite nut drivers to convert them to spanner wrenches for various projects. The hollow-shaft drivers would be a real advantage, since the Xcelite's that I've modified have solid shafts, and are a real pain to drill out. Fortunately, I've had a ham on the Collins Collectors forum volunteer to loan me his Collins tool. Pretty darn generous of him.
Thanks again, and I'll likely fashion my own tool using your suggestion, for any future needs.