Well, I've been driving w/out the limited slip additive in the Moser, and geez the posi chatter has gotten really loud!~ I mean it would chatter and grind around even the smallest turns. So I finally broke down and bought a 9/16 hex so I could take out the fill plug and I put the additive in it. After letting it warm up for a few minutes I went for a drive, and almost all the chatter is gone. I can still slightly hear it on tight turns, but it's for the most part gone

So for anyone installing a Moser, I'd definitely recommend putting the additive in your rear!