Symmons Allura Tub Faucet

Hey Guys,
I've got a Symmons Faucet on my upstairs tub/shower, and I've noticed a problem with it lately.
I removed the handle, escrucheon and the diverter key and I noticed that when the faucet is on and water is flowing (especially when diverted to the shower), a slow trickle of water comes out of the diverter keyhole and in my case was dripping behind the vinyl wall of the shower.
So I went out to home depot and bought a washer replacement kit specifically for Symmons repair and it had the washers that could easily be changed. I followed the directions to disassemble the faucet stem and I was able to replace the hot water washer since it was only held down with a screw, however, the cold water washer was held down by a collar that is screwed in place. The instructions said to remove this with channel locks, but for the life of me, I couldn't get it to budge, even after applying some WD40. Has anyone had luck removing this bad boy?
Anyway, I put the whole thing back together without changing the cold water washer and I still get the same problem.
Does anyone know where my leak is really coming from?
I also bought a new diverter valve but I was not able to remove the old one, even after removing the plate that holds the diverter in place, I just couldn't pull it out and the instructions didn't give me any clues on how to do that.
Anyway, I guess you have to be familiar with a Symmons faucet system to even know what I'm talking about. Any help you guys can give me would be greatly appreciated.
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