Removing the distributor on the 226 is a simple operation. Like the shop manual notes, there's an oil pump that has a tab on the top end of its shaft. That tab fits into a slotted adapter shaft that drops in from the top of the engine. The top of the adapter shaft is slotted and the bottom end of the distributor fits into that slot. The slot is offset so you cannot put the distributor on incorrectly.
To remove the distributor, remove the wire lead from the coil, the vacuum line to the advance, and the 9/16 bolt attaching the unit to the head. It's also easier if you remove the distributor cap, this way you can leave the wires intact and not have to worry about getting them back in place in the right order. Then, simply remove the distributor assembly as a whole. The adapter shaft may lift up as well, just wiggle it loose and drop it back in place exactly as it was. It does not need removed.
Distributor main shaft wear was and is still a problem with the distributors, both Autolite and Delco.