Extra Spacer After Replacing Center Bearing

[too_cool_mitch]

Hey everyone I was wondering if anyone has done the center bearing recently.. my problem is I just replace mine on my 2001 Chev 2500hd 4x4 8.1l with the allison transmission. After I assembled the 2 piece drive shaft to install it back on the truck I noticed there was an extra spacer looking thing that I thought went in the end of the yoke that goes in to the transfer case.. unfortuneately when I put it in there to reinstall the shaft would not slide into the transfer case with the spacer on there.. so I took it off and tried to install it between the slip shaft between the 2 drive shafts... it would not fit there either since it wont slide over the blue coating prop shaft but is almost the exact size as the other halfs opening in diameter.. I installed the driveshaft with out this spacer and everythign seems alright but if someone could tell me where it goes I'd like to do it the right way... Anyways hope someone can help. I'll try to take some pics tomorrow and so you can get a better idea of whats going on. Thanks