The finder on most of these automatics is going to either be a single window “distance estimator”, like the 104, or with a double window for focus/composition. The third kind, the metal Zeiss Ikon finder, is only found on a handful of them.
Either one, probably needs a good cleaning. Depending on which kind of finder you have, the removal may not be necessary or even possible. However, each finder can be opened and cleaned. If you can remove it, it makes cleaning it and the camera alot easier.
This single window finder is held in place by a single screw found within the film back. As you remove it, take note of the small plastic tab in the front which is inserted into the rails of the focus bar. This is what moves the distance estimator within the viewfinder as you move the focus rails left and right.
If you can’t remove the finder, you can still open it. This one has 2 screws on the back. When loose, do not try to open it. Turn it over so you are looking at the “front” and open it, or the mirrors inside will fall out!
Its not hard to recognize what goes where in this simple setup. Remove the 2 mirrors and mask and clean them with a lens cloth. Wipe the insides out of any dust and also clean the eyepiece on the inside and outside. Alcohol, Q-tips and elbow grease work best.
Here you can see the little plastic tab which inserts into the focus rails and moves the distance scale.
Clean all the surfaces you can.