I did it! With some help from YouTube. I took the passenger wiper arm completely off. Meanwhile, I also lowered the wiper on the driver's side so that it's more in the 'bubble' and catches less wind. Thanks California98Civic for that idea!
I will also swap the current 20" wiper by a 26" one, to make up the loss of the other one (a little). It should fit.
Wipers where in need of replacement, it will now cost me less and thus compensates for the purchase of the grill cover
Technique of removing a corroded wiper arm (see photo's below or the movie on YouTube that helped me
- Screw another bolt onto the post, 1/2 to maximum 3/4 (to protect the thread)
- Place a wrench or pincers under the arm to apply upward force while hitting the bolt with a hammer.
Rusted grit is released and after another few hard strokes the arm comes loose.