Settle down Beavis. 250's are welcome here.
Quick change clutch cover? Simple. You'll need 2 covers, a mill, a cuttah, a welder, an o-ring, and some bolts. But is it really needed?
What about the brake lever?
All that stuff billet? Gonna be $$$$.
I've got the basic LT380R plan done for you. Still need to work out some crank pieces, and measurements would help in other areas, as in seeing if the cases can be mutated enough to use a bigger yet strangely similar cylinder. The problem is that slant. If it stays, the piston/transfers won't line up. If it goes, the frame tube is in the way. I'd rather screw with the frame.