Getting the outer end shorter is not a problem, either by cutting a little of the blade or by getting an adjustable wiper arm. The problem is the inner end that will seriously foul the lower edge and even the scuttle due to the sweep angle. At least on my car, anything more than a sweep angle of say 100 - 105 degrees will not work. My car has an angle of 130, so I have some work ahead. CBS has wiper gears down to 95.
My path wil be as follows: cut the outer end of the CBS 8" blades to gain aprox. 15 mm (already done). Next get adjustable arms and extend them untill the outer end nearly touches the upper and/or lateral edge of the frame. By this I should achieve maximum possible distance between the inner end of the wiper and the lower frame edge/scuttle at full sweep. Then get a protractor and measure the maximum permitted sweep angle that will not foul the lower edge. So, get a new gear with a hopefully correct angle and install it. The reason I go through so much effort with first cutting the blades then elongating the arm etc, is that I want to maintain the swept area on the passenger side as much as possible. By this I should gain some area as opposed to just changing the wiper gear.
