Just finished my second conversion.
This one was a Zeiss ZF 28mm f/2. It's the old version without the electronic communications to the camera, therefore I did not have an "aperture lock" to remove AND it did not have the 3 tiny washers under the Zeiss mount that the newer ZF 21mm f/2.8 lens had.
To my surprise this one was completed in only about an hour, if I was not so slow/careful/clean I bet I could have done it in about 40 minutes.
I sanded this one down .23mm. I'm getting better at sanding down exactly how much I want to take off now.
Just like the Zeiss ZF 21mm f/2.8, when I mounted this lens on my K1 it fit PERFECTLY and NICE AND SNUG. Love those Leitax mounts - certainly premium quality!!
Just shot a few test photos outside, and they turned out great, even at infinity.
I have no further plans to convert any other Zeiss ZF lenses. I do hope that the experiences that I've shared here will help you to do your Leitax conversion. Just take your time, and I fully expect that you'll achieve the same great results that I did.
Dave in Wisconsin USA
P.S. I did NOT loose the aperture bearing this time.