Thanks Dale and Don
So I re-did the RA today. One of the gears in the RA gearbox had by far the most dried on grease on it. In the end, having assembled it all again and with a counterweight and my scope back on it, it sound like butter on both axis in both directions, I am very pleased. The PE curve will be fascinating to see when we have stars in the sky again.
The regrease instructions were a bit brief for me, a software guy who has never done anything like this. I wasn't sure how much grease to put on, the instructions say less but more evenly applied is better than more but less evenly applied, but not really how much. When cleaning the old dried grease off I kept imagining the mineral spirits and denatured alchohol running down the face of the wheel and into the main bearings, I have no idea if this is a silly thing to worry about but I worked to keep any excess from going far. I wondered what it takes to noticeably upset your PE, would a hair on the worm wheel do it, a speck of old dried lube etc. It's fun to do new things but having some knowledge about it would be nice.