I've been watching these posts intently for the last few months.  I've been hesitant to post, not wanting to distract the AP crew from their excellent work.  However, I find myself in much the same situation as Dean Jacobsen, having signed onto the Mach 1 list in October 2018 and later also opted for the low temperature encoders. 

I'm not particularly knowledgeable about these things, but still I wonder why they should be more difficult to install?  I would think they would be a simple drop-in replacement, having only an upgraded optical component. 

(I also wonder where I am on the list, I've been without a useable mount for a long long time.  :)