Heard a rattle so I lowered blower and unlocked pins, slid collar on small blower shaft with universals that connects to the mid PTO shaft. Backed up tractor a bit to check blower, and the spline separated from the shaft on the blower drive shaft. There is a small Allen screw in the blower shaft. I looked at the splines and can see two with a small bridge(not damage, factory machined like that) it looks like the Allen set screw hole is suppose to be aligned with those two splines. Didn't take any pics before this happened. I slid blower shaft back on splines and set Allen acre. I don't remember if splines are suppose to show ? Mid pto collered on drive shaft properly, hex end thru bearings but when I attach blower drive shaft, splines are showing. Don't want to screw anything or cause damage if those splines are not suppose to be showing. It doesn't appear mid pto drive shaft is telescopic. If I put the blower drive shaft back together so no splines show, the blower shaft locking collar end won't reach the spline end of the mid pto drive shaft.