Yeah, I used a bit of the wooed against metal. They are a normal universal type configuration but once I took out the long screws, it was a battle to separate the halves. The stupid part is the pulley was tight and then after I removed the screws it loosened up. However, the long screws have nuts on the ends and the nut on one side is under the Pfaff label which wouldn't come off. I finally got it apart last night and it involved using a clamp with wood blocks and a chisel...to a screwdriver, to other objects to wedge in the slowly expanding opening and twist.
Once I had it open I cleaned it, checked it over, and it was a nightmare to close. Now that it's closed, something it rubbing. I think one of the wires may have slipped into the way.
So I am going to have to open it up again today. *sigh