I think you could try taping your lens onto the M42 mount or try any other 'diy' solution as this will be a totally static setup at home, right ?
I am sure there is an optically best way to do this, but I don't really know which :-)
Here's what I did lately. I took some pieces I had and gave it a try.
M42 distance rings + CZJ Sonnar135 + achromatic near lens (+1.7 ?) + long lens hoods
Put this combo on a tripod and directed it onto a light box.
Results were as good ar as bad as the slide, quite good imo.
This was easier than I thought and it's a nice winter activity.
Best of success,
Georg