I just realized there is a seal I did not purchase yet, the 5th gear seal (pn 12035B). Youtube sure helps!

 

That seal is leaking, you can see transmission lube leaking between the main drive gear and the mainshaft:







Here is a pic of that seal and where it goes:




I suggest you replace all the seals on the transmission while the inner primary cover is removed:

Quad Seal
Pulley Spacer
Big Oil Seal
Shifter Shaft Oil Seal
Main Drive Gear Oil Seal

Inspect the shift lever splines and the shifter shaft splines carefully, and when you reinstall the shift lever use a new bolt and make sure it is tight.

OP: What model year transmission is this?

 

2001 Road King police
5 speed trans.

Pulley spacer? Is that the SS part with the chamfer? Why should I replace this?

 

Here's a proposed sequence:
1. Remove trans mainshaft seal
2. Remove and replace quad seal
3. Re-install trans mainshaft seal
4. Remove and replace 5th gear seal
5. Re-install trans pulley
6. Install inner primary race

Etc.

 

How many miles on the pulley spacer? Unless it has very low mileage, I would replace it.

The outside diameter of the pulley spacer is a sealing surface, it rides against the big oil seal.

Replace every seal (post 22).

 

50k.
I guess I can pick one up, can't hurt.

 

This helps:

 

If the mainshaft seal is leaking,the drive belt will have oil on the tooth side of it.(inside)

 

No oil on the belt. I'm pretty sure it was the 5th gear seal and shifter shaft seal.

 

Looks like the IPB sleeve wasn't in all the way.. Also the Pink spoo seems to be sayin' the mainshaft seal in the main drive gear ain't doin' it's job.. I'd check for play. It's possible the mainshaft needles have walk in. Also it looks like the mainshaft seal is missing but it's hard to tell.