Not worth it? Of course it is! :wacko
I did this very thing, put in 06 1000 cams, coated the pistons with thermal and friction coatings, have a full yosh exhaust, and used the stock 600 sprockets. Its pretty fast!
The 750 motor will bolt right into the frame, but the 600 header will give you some flack where it bolts below the right foot. With the muffler installed you just need to pull back on it a bit while you get the bolt in.
You need the 750 engine including airbox, and you need the 750 ecu. Some people have used the 600 airbox on the 750 motor, but I believe it is a hassle because of the velocity stack and throttle body sizes.
I did this very thing, put in 06 1000 cams, coated the pistons with thermal and friction coatings, have a full yosh exhaust, and used the stock 600 sprockets. Its pretty fast!
People also think you have a 600, so the sleeper aspect is fun.