I struggled mightily to find good step by step directions on how to do this. I rummaged through site after site, lengthy detailed explanations, conversion directions, etc. But every place I looked (and this was days of hunting, reading, trying) refused to give up the secrets.
There was lots of mention of nulib and even nulib2--and a version on the Macintosh. One came with the OS XII emulator in its miscellaneous folder. But how to use it? Double-clicking launched a Terminal window and provided a list of commands-- but then what? There is a real need for a front end GUI for this folks!
In any event, after much trial and error, here's what I figured out. It's a set of step by step directions on how to expand an .shk or .sdk file on a Macintosh using nulib2. I've even tested the directions as a novice would reading them for the first time. They work! But if you find a glitch or an error please post a suggestion or correction!
To keep this post a reasonable length, I'll put the directions in the next message!