In Conclusion
  The new block lived up to my expectations in ease of installation, adjustments, and performance. Oh yes, and the 21st century V2 look too. At first the results had me concerned because of a new peak but realizing that with a new block design comes a new method of installation and adjustments due to the Ruland disk coupler used in place of the Oldham coupler. There were no instructions with the unit and as intuitive as the installation may look, worm to gearbox alignment is critical to remove the 'pulsation' felt when manually rotating the worm where the previous Oldham coupler was more compliant in self adjusting though you could still be out of alignment. Once the alignment was perfected the performance improved and exceeded my expectations as can be seen below with the before and after profiles. And because the 76 sec error has shifted to a fundamental frequency (80 seconds) it was successfully reduced using PEC programming.

   Coupler Design- If you are a diehard and want to use the Oldham coupler you need to get a longer gearbox drive shaft otherwise you will have to use the Ruland coupler that came with the new worm block. The test results of the Oldham and Ruland couplers show that both perform equally well when properly aligned so there is no advantage of staying with the Oldham coupler.

So, getting back to my original expectations:

• Reduce or eliminate the 76 second error - The 76 error was reduced to less than 1 arc second peak due to more accurate RA component alignment. It was reduced further to near seeing limits of .2-.3 arc seconds with PEC now that it occurs on the 80 second fundamental line.
• Improve PE tracking - PE has improved substantially and consistently through better alignment of bearings, motor and worm. Though the worm determines the PE profile, eliminating outside contributing errors helps by not showing up in the net PE curve. This also has allowed much longer guide star exposure capability, something that will be appreciated with narrow band imaging.
  The +/- 3 arc second PE before PEC and under 2 arc seconds with PEC enabled places this mount in the category once dominated by much more expensive mounts.
• Ease of removal, installation and adjustment - This new block design is not only easy to remove, install and adjust but it also maintains repeatable PE performance each time. This is due to positive bearing block and gearbox/motor alignments.