I'm also updating my MAME entry, once I've got that done you should be able to use it to initialize your CF card however you want.
https://www.savagetaylor.com/2018/12/26/setting-up-your-vintage-classic-68k-macintosh-using-mame/
https://www.savagetaylor.com/2018/12/26/setting-up-your-vintage-classic-68k-macintosh-using-mame/

