I reckon that's true enough. I followed 50456 for a LONG time and never thought I'd have the opportunity to acquire it, but persistence (and continual reference and queries about previous posts, photos, and info from other venues) finally brought it home. And thanks for the kind remarks.
So this one is a bookend for the upper range of the B series? Is there any additional info at this time from primary sources regarding the startup of serial production of the M59? And as far as you know, is SKSDude's 15001 the low end?