Finally started this project a weekend ago, This is a challenging build as the cr250 motor doesn't fit in there like a cr500 motor, the clutch case seems to be farther back on the engine block causing interference to the loweer right frame rail and the frame casting. I approached the problem by setting the motor as far foward as possible and attaining a good countershaft center to swingarm center, im about 1-2 mm's above center.The exhaust is lining up well as is the airboot, looks like i will have to cut 1 mount from the silencer for relocation to make it work.
Here's a some pics of what i have so far,