Thanks for the help. I don't have the Mac or its drive with me right now, but I'll double check the connector when I get the drive. I see several Adaptec 50-pin SCSI cards on ebay for around $10, which are apparently supported on XP.

I use HFVExplorer to manage my HFS volumes for the emulators. It does both reading and writing, although as you say I only need reads in this case anyway.