Thanks for posting the photos. They are excellent!
It looks like Tucker used identical parts as far as the wiper shafts and linkage mechanism as well as the wiper motor and transmission. Yours look pristine, BTW. (Though the linkage arms are likely different lengths if your cab is 48" wide.)
In the second photo you can see the wiper motor, and above that you'll see a silver domed metal cover. It's attached with three machine screws and the cover itself has slotted holes through which those screws pass. If you loosen all three screws, you can rotate the cover a little bit.
Rotating the cover adjusts the park position of the wiper blades. There's some trial and error in finding the optimal park position, and it's a pain to get one's body in the right location to reach those screws and turn the cover. I recommend having someone else on hand to help.
The wiper arms are held onto the wiper shafts with acorn nuts. If you remove the nut, the wiper arm should pull off. There is an aluminum splined conical frustum (a cone with the top missing) with an elongated center hole. Sometimes that stays on the shaft, and the wiper arm comes free, other times that part comes off with the wiper arm. If you need to re-position the wiper arm, you can separate the wiper arm from the conical frustum and move it however many splines you need to do so.
If your wiper arms are rotating too far (or put differently the angle subtended by the arc is too great), that too can be adjusted. The fourth photo shows the attachment of a linkage arm to a wiper shaft. You'll note the linkage arm attaches to that wiper shaft with a clip. If you remove that clip the linkage arm can easily be removed. That will reveal the pin the clip attaches to.
In the same photo you'll note two additional elongated holes. If you remove the wiper shaft from the Tucker (remove the nut outside the cab) you'll see the pin used for the linkage can be relocated to either of the other two holes. (It's held in place by a nut that you can't see in the photos.) As you move the pin further from the center of the wiper shaft you will reduce the amount of arc the wipers travel.
In proof-reading my post it sounds complicated, but once you start taking it apart it will be pretty easy.
Good luck and I'll try and answer any questions you have.