To install your override you have to take the motor out the frame and split the cases. That means complete disassemble of your motor. The benifits are while the person your racing is having to pull the clutch in to shift all your doing is pulling the clutch up spending no time to shift, easier shifting (when a lockup is installed) etc.
I would find out if you have a lockup installed under that cover and if you do i suggest you REALLY look into getting a override put in that motor. You have alot of potential to have a nice dune drag bike from the looks of your bike.
As for as the paul turners i have no idea how much you could sell them for i don't read to much about them or look for them on the site. But IMO i wouldn't go flat track only because of what you have done to your bike so far.
Like dajogejr said a nice set up cpi inframes would go nice.