Windshield wiper woes

[stickshift]

Well, I'm down to the final repair on my recently purchased '31 truck. The windshield wiper would only oscillate once when actuating the knob, so I sprayed some light oil in the vacuum hose inlet as I've read done in previous posts and let it sit overnight and that did the trick. The rubber was gone on my wiper blade so I ordered a couple replacement blades. When they arrived, they were different than mine. Mine says "dead-lock" on the bracket. The new ones just had a couple holes in the middle of the metal part of the blade with no bracket and couldn't connect to my wiper arm which is just a "J" shaped hook. So, what I had to do was remove the rubber from the new blade and pinch it in my original blade. For the life of me, I couldn't get the "hook" of the arm back in the dead lock bracket on the old blade even though it came off easy with a little manipulation. I resorted to removing the dead lock bracket and re-crimping it to the blade with the wire arm attached to the bracket. My question is: What is going on here. I can't go through this every time I change a blade. Is dead-lock a normal wiper for AA trucks? My wiper motor and arm look original.