I have a Naomi with a Netdimm that I’m not using yet. Want to make a multiracer, but not sure if I have the right cables.
All you need is a JVS IO board, I'd suggest the Sega IO , ver 2 or 3. With a NetDimm that'd get you Crazy Taxi, Jambo Safari, F355, Faster Than Speed, and Maximum Speed. 18 Wheeler wont work it either has a funny wheel or weird gear pinouts.
If you upgrade your Naomi1 to a Naomi 2, then you can add Initial D 1,2,3 and Club Kart. Though all 4 of those really require the card reader to fully enjoy.