I only have first hand experience with the 800's but on them the slip joint on the rear of the driveshaft (transmission) has enough room to let you slide/tap the driveshaft back once you remove the roll pin from the from pinion shaft. Slide the driveshaft back, get it off the front input shaft, then slide it forwards to get it off the transmission output shaft. Seems like I've read that the 900's are the same.