Originally Posted by
base2
What I see going on there is a potential for the nut that holds the hanger to interfere with the smallest cog or the chains engagement with the smallest cog.
Or for the RD upper bolt to bottom out on the cast hanger.
I still think the classiest way about this would be to 3D print an alternate Shimano upper tab designed to work around the Simplex dropout. Definitely the least cost effective, but without a doubt, classy.
-Kurt