Well, don't want to be a party pooper, but don't be fooled that easy collimating a CDK 12.5 is a given.
My CDK was a nightmare, and my friend Josh above, is also suffering with trying to achieve acceptable results. Those with an APS sized chip slip through issues full frame users get plagued with. Mine needed heavy modification to provided balanced results in all viewing orientations. Soon as you do a camera rotation with meridian flip - collimation was different, and image quality suffered.
Watch out also for the arm chair advisors who insist your problem is CCD tilt. With a massive CFZ, it's often unlikely with quality fittings and an STL (but not impossible).
Good luck, and hopefully you got a good one, as its all in the assembly most of the time with these scopes, as individual parts are normally precisely made.
Steve
