I purchased a second hand C8 Ultima (blue with bright star coating) that I had to collimate. The corrector plate was oriented such that the Celestron logo and a little rectangle for what could have been the serial number label were not horizontal as I would have expected to be when new. They were oriented about 30-40 degrees CCW.
Since as a read, corrector plate orientation seem to be important I wonder if those of you who still have the plate in place from factory or have put it back in the same orientation as from factory can confirm if the logo is horizontal when the scope is in home position.
I am curious to know if that can be used for reference to orient the corrector plate. I looked around the edge of the plate and saw no marks when I removed mine for cleaning.