+1 on the extenders, I used to ride pigeon toed before, now my foot position is where it should be.

 

The difference might be the dash or panel on the tank. I know that ont he older models that there is a difference in the length of the dash. The electraglides have a shorter dash too them which means the nose of the seat is a little longer. So if you put a street glide seat on an electraglide then you have a big gap between the front of the seat and the dash panel on the tank. If you take and electraglide seat and put it on a Streetglide then the nose of the seat would extend up and over the dash panel.