[JoeG]

If that wy is really a wj, then it could be a '72 M22....
Up to '70 the M22 had fine splines on the output shaft---After '71 they all changed to fine splines on the output shaft----The '71/'72 M-22 had no id rings on the output shaft ---take off tailshaft housing---Or see if you find John Brown's recommendation--the letter C after the numbers would designate M22...