I would put the stock seat on and even pad it to raise your butt, if you can still reach the ground
like SEJ i ride jockey style with butt in the air a little ,
on the salt we get more time to experiment and find the sweet spot
Single ride that taught me the most about body position was when Garry Peterson (Gazza414) let me ride his mildly modified busa in 04 , once at speed every change made a difference in rpm , elbows in , butt up, toes in , head and back at the sweet spot
where you can just feel the wind but your not fighting it
And i agree with all Jims comments and will add handlebar , you can shorten them and get your hands within the air bubble of the bodywork , brake and clutch can mount on the other side of the fork clamp if you push the bar through