On my search for KIM-1 software I stumbled across the Pocket Calculator for the KIM-1 by Siep de Vries.
You can find the documented sources on hansotten.nl (as always).
I was typing and compiling the program for a whole week, till I found all typos. Some minutes after I published it, Hans himself told he already gave it a try last year (and did not publish it yet) and presented his 1:1 copy of the program with no typos and full documented sources....
You now can find the program and the sources on Hans' Website, and my humble tries on my git....
another piece preserved Yours webdoc