From the parts diagram that someone linked in your other thread, it appears that plate is covering/holding the seal in place.
Have you popped it with a punch/chisel? Carefully, but it sometimes takes an impact.
I have not myself changed the seal in question. Hopefully, someone who has will verify.

 

That's the release bearing guide. It has the seal as part of the metal housing..you may just need to tap it with a hammer to get it loose, but once off you will see the seal..easiest thing to do it get a new guide and it comes with a seal as part of it

 

I tried hitting it with a rubber mallet and was unable to get it to budge. I decided to skip replacing the seal and put it all back together. The clutch and trans worked perfectly but right away I noticed that it was leaking trans fluid out at the junction between the engine and trans just like before. I'm going to pull the trans again and make another attempt at accessing that seal, but the rubber mallet was starting to deform the release bearing guide and it was not showing any signs of coming loose. I'm not sure where I would get a new release bearing guide, if you can point me to a source that would be helpful. I don't see one at ECS Tuning which is where I normally look for parts. Another part I'm looking for is the intermediary piece of metal that connects the transmission to the transmission mount.

 

http://www.pelicanparts.com/catalog/SuperCat/VW1K/VAG_VW1K_TCLUTC_pg5.htm ..the guide is down towards the bottom of the page....you could also try sticking a screw driver in-between the tube and input shaft and popping it loose there too

 

Thank you! I've been googling around trying to find more parts sources but had not come across that site.

 

You're welcome! Yea there are quite a few out there and not all of them come up right away if you try using Google to find them

 

I pulled the trans again and managed to get the bearing guide removed by prying with a couple of sharp flathead screwdrivers and a little sharp hook-shaped tool. I've installed the new seal and cleaned up the metal mating mating surfaces. Whoever had last installed/re-installed the bearing guide had left the black rubber o-ring in place and had also added a thin layer of silicone adhesive. After trying to clean the adhesive off the o-ring I decided to scrape it all off and get down to the metal using a flat file and wire wheel. It did kind of look like trans fluid may have been seeping through at the bottom edge of the o-ring/silicone mess, so maybe the input shaft seal itself wasn't the source of the leak but rather it was the bond between the bearing guide and the trans housing.

Now that I have the metal mating surfaces cleaned up I'm planning to seal the outer edge with a silicone adhesive. I happen to have some Permatex grey gasket gasket maker around from the last time I replaced my oil pan. Would that be a suitable sealant here?

 

Yea that'd work fine..just try to clean the surface as good as you can so it makes a good bond and you should be all good