I hope he doesn't take 3 years (as I did) to give up the ghost on that ##%^$^ wiper cam!
I can't post on that board but here's the pic of the wiper cam mod that he'll need to make to overcome this disaster.
All you need to do is weld the pieces from a 76-77 to the existing 1978 wiper motor offset piece and the corresponding small end on to the big end of the linkage rod going from the wiper motor to the first pivot. It's literally a 30 minute fix now.