I know the better solution to use this lens is to get a ZI/Hexar RF/Leica M.
Unfortunately, I only have CLE....
I will find another body for this lens someday.
When I put hex 50/1.2 on CLE, it comes out 40mm frame line.
For me, it's easy to guess the 50mm view.
Yes,it blocks rangefinder about half and is really hard to focus at first.
But once you get used of it, you'll find it isn't that hard.