What seats will fit 79 kz 650 d2 st

I have a 1979 KZ 650 D2 Sr. As you can see from my user photo someone before me swapped out the painted fenders for Crome. My question is I would like to add the rear seat faring duck bill whale tail thing and the flatter seat from say a b or c model what do I need to do it and can it be done? I always thought that rear faring is what made a KZ look like KZ

You could do something like this.....

The rear part of the KZ650SR frame is different from the other models.


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