Jack the rear up so the driveshaft will turn..Remove the shift rods and see if you can get neutral by manualy moving the side levers...Might have missed a shift hub while apart...remove cover..have the driveshaft so it will turn...Move each slider untill drive shaft turns. Now you have neutral....Shift the cover levers so they are both on the center detent .you now have neutral...Carefully install cover making sure each fork is in each hub correctly...Install two bolts hand tight..Shift levers to see if driveshaft locks up and frees up when each lever is in the center detent...you now have neutral...

If all the cylinders ain't in a line it ain't cuttin it..