Well, after finally getting her back on the road and using daily, I find leakage out the rear seal. At least it's not the front seal! Anyway, I've read the manual and everything seems pretty straight forward, but I'm experienced enough to know that's not always true. Any tips, tricks, etc? I've already had the rear funky mount off and replaced the spring amt rubber donut, and had the pan off twice, so I already have that experience. Just never had the shaft out, etc. Anything else I should replace while I'm at it.

 

Mark the position of the center bearing carrier before you remove the driveshaft.
You will notice that the driveshaft is not centered in the tunnel at the point where the carrier bearing is located.
Aslo look for additional shims where the spacer goes between the body and the center bearing carrier bracket.
Mark the flange at the differential so you can put it back in the same position.
Other than that, the rest is normal procedure.
Note: Driveshaft is very heavy.

 

Sanchez - why do I have to remove the driveshaft?

 

The rear transmission oil seal is the mechanical seal between the rear of the transmission and the driveshaft yoke.
You stated in your post that you had a leak at the "rear seal". Unless you are talking about something else.
If that is really the case, you will have to drop the driveshaft to replace the rear seal.
Look at Item # 6 in the photos attached. This is a Series 3 66 transmission. Yours should be similar.
That is where the driveshaft yoke slides into the transmission.

this is where the rear seal is located

#6 rear seal

 

If the rear of your transmission looks like the part circled in red below, you will have to remove the four bolts at the flange and see if the driveshaft will drop out of the way so you can change the seal. Either way, that is where the rear seal is located.

 

Yes to all of the above. It's close but I figure if I remove the pan to the left in the picure, the drive shaft will drop low enough to be out of the way. Yes? No?

Block of wood is only to hold the driveshaft up

 

Probably. The driveshaft still has to move back some to clear the flange of the driveshaft from the yoke flange that is going into the transmission. The yoke flange on the transmission is held in place by a nut which you will have to remove to get the yoke out to access the seal. See image with green circle.
The front part of the driveshaft with the u-joint and the rubber boot (where you have the piece of wood) is splined. You should be able to slide that piece into the main driveshaft to shorten it.

 

Yes, already removed that bolt holding the flange on the transmission and it slides easily rearward. Just need the room to get it out. And I looked at pics and saw the splined forward driveshaft piece. Hopefully by removing that shield everything will be easy ( yea, right!). Thanks for the sage advice and encouragement.

 

If you plan to slide the forward piece back, you will have to loosen/remove the clamp on the rubber boot. Without loosening that clamp the forward piece will not slide back.

 

I figured it should have a clamp but it doesn't - not good. Dirt and stuff can get in there. Will clean it and grease it. Will have to get a clamp before putting the whole thing together.

 

If removing the shield does not work, mark and lower the center bearing. That will cause the driveshaft to bow moving the front backwards.There is a u-joint at the center bearing.

 

Removing shield allowed this... Second pic, job done. No big deal.

 

Nice!