I noticed on the data sheet that this grease is not recommended "As a lubricant in metal bearings"
I emailed Daleen instead to place an order for the AP special grease.
Also, when I took DEC apart last night I found that one of the little clutch plug tips was crack and wedged in the last threads. I had to really force it out, so I kind of doubt it was doing much other than just being stuck.
On another note, I love the simplicity of this mount design. I've rebuilt Orion Atlas mounts before when I hypertuned them and this 400GTO is so much better internally. The quality of the components and machining as well as the decisions for how to put it all together are so well thought out. As Roland said this is a 30 year old design!
The good news is that the grease looked old, black and tired and I think a full service is in store. I suspect that most of my challenges with this new to me mount are likely service related.