Søren, I use a Minolta Compact Bellows on my Nikons.
At the rear, the adapters are Novoflex LEIMIN (female MD-to-male LTM) and Novoflex NIKLEI (female LTM-to-male F).
At the front, since I use Luminars with a female RMS-to-male LTM adapter there's a Novoflex MINLEI-P (female LTM-to-male MD). There are also MINLEI and MINLEI-K. -K is for kurz, and the -P is orientable like, e.g., a T-2 mount adapter.
If I want to use Nikon lenses on the Compact Bellows, I could put my female F-to-male T and female T-to-male MD adapters on the front.
All of these adapters -- I also have female MD-to-male T and female T-to-male F -- except female T-to-male SLR are hard to find and usually expensive. I was very lucky to have got my Novoflex adapters as cheaply as I did, but it took couple of years. And I was extremely lucky to have found my reverse-T adapters.
One of my neighbors also has a Minolta Compact Bellows that he's adapted to C/Y. He replaced the mounts with C/Y front and rear mounts. How, I'm not sure; when asked he mutters something about screw holes matching up. If I were going to go that way, I'd start with a cheap used Nikon E-2 ring and drill holes as needed. Much less expensive than adapters, and faster.
Bellows that aren't made for whatever system on has standardized on are too expensive even when free. I knew that when I got my Compact Bellows.
Good luck, have fun,
Dan