slip yoke on a 904

How for out does a yoke have to stick out the tranny.my yoke is about 5 1/2 inches long. The yoke is like 3 1/2 inches in the tranny and sticks out 2 inches. I've heard its supposed to be 3/4 out but if I could use this drive shaft I won't have to get one made up. When its bolted up it seems like its in there good no slack or wobbling at all. What do you guys think
Author: martin53