Can I install the modification kit on a Contax N lens by myself ?
No, unless your profession is electronic camera repair. This is not a DIY installation. There is no reason to put an expensive lens at risk. Pay a professional to do it. I am explaining all the complexity of the installation to you in great detail so that you do not attempt DIY, although all these are second-nature to a competent repair professional. We have had a customer report of a failed DIY attempt. Please don’t try!