I have a Sinar frankenrail...it's an extension rail that was sort/kinda turned into a base rail by somehow lengthening the center screw. It looks like this:
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As you can see, it stick OUT of the rail....where a proper extension rail center screw is slightly recessed.
I'd like to cut that screw back so it is properly recessed (or replace it with threaded metric rod of the correct length)...but I need some kind soul to tell me how far in the end of the center screw is recessed. Thanks in advance!