80 kz1000e shaft rotor (generator) vs. 81 KZ1000 J

I have 80 KZ1000E shaft with bad generator rotor, I would like to install rotor from 81 KZ1000 J model.
According to bikebandit diagram rotors and stators are different. I hope that if I replace rotor and stator with cover, it will fit.
Tomorrow I am going to buy 81 frame with motor, so I can use parts from there.
Starter sprockets and needle bearings are the same for 80 E model and 81 J.
That means cylindrical part of crank under needle bearing has same diameter. the only question is if tapered end is the same. If it is, 81 J rotor will fit 80 E crank
Any thoughts? Thanks.

This website may be of help to you. If not for the valve....other stuff.

www.zedder.com/