They say to use 2 pump shims instead of one to give a little extra clearance. One is only .001" thick. I put 2 shims in my 3240 just for the extra insurance so I would not have a problem in the future. The person that told me this got the advice from a factory person that worked on this issue from Cub Cadet. I took the fender off but wondered if I could have done it the way you did. Mine has the cast iron rear and this unit sits down in a bit of a pocket. If yours has the aluminum rear it may be different and easier so you would not have to take the rear fender off. Just make sure you get the gerator housing the right way or it won't work. Found the picture and this is how it is installed looking from the back forward. I got my parts from the company shown on the picture.
