New to the forum 73 Dart
Ima thinking that pulling the axle , even if it was possible (only on a a C-clip axle) won't work, cuz the backing plate is till attached to the rear-end housing, with the brake-shoes still anchored to it. Ima thinking that would be a waste of time.
I'm afraid you'll just have to try harder to disengage the self adjuster blade.
I have, on occasion used a cotter-pin puller. This tool is like a screwdriver, but the tip is bent over at about 90*s. This allows inserting the tool over the adjuster, then rotating it downwards between the adjuster-body and the blade. Now all you gotta do is push like 1/8th of an inch, then have at the adjuster. If it is seized, which happens a lot, well then, on to plan B or C :(