Leica 35mm Summicron Version 1 - Weird Location of RED DOT???

[HuubL]

My V1 Summicron is like Peter's, small dark red dot on the polished lens mount, but without a set screw. OTOH, my Summaron with the large dot on the satin chrome does have a set screw in the polished mount. That wouldn't mean the M mount is removable to convert the Summaron to LTM, would it?