quick d 17 question

I know that a ring and pinion gear out of a series I D17 will fit a wd 45. Does this include the series II rear end. I have a rear end with the serial number 40069 which is toward the end of series II will it work? want to gear down the wd 45 for dead weight pulling

According to AGCO Parts Books.com.....all D-17 ring and pinions are the same from first to last series(70245766 p/n). I do know there are two different input shafts and countershafts and second and third gear width combinations over the years and the countershaft was made longer, but somehow, they managed to keep the ring and pinions the same. Now, on a dead-weight pull (which I've never done) I cannot imagine ever needing a gear slower than 1st gear. Any good running WD-45 can't be stalled in 1st gear unless it weighs 5500 pounds or more with standard tires on the rear. Where am I wrong here ?????