OK, so I removed the case of the original hard drive, and as expected, the rubber stoppers for the drive head were a gooey mess. I tried cleaning with ISO alcohol, but the stickiness remained. So I put some kapton tape over both stoppers. Fortunately, I was able to boot off the original hard drive. It was running 6.0.7, but I couldn't find any radius extension / control panel in the System Folder. However, I at least was getting some video out from the Radius card, just nothing my LCD with VGA input can seem to handle.
However, I'm hoping to get it running on 6.0.8 with the latest software. After reading more info in the Installer from macintoshgarden, it looks like I need the version 4.4 ROMs to use this card with the latest Radius software. The ROMs I have right now are for 4.1.
Anyone have the ability to flash some ROMs for me at a reasonable cost? Not sure how much I'll be doing, so purchasing a programmer, along with learning how to erase the EPROM (UV light, I believe, so could I use my retrobright UV box?) probably doesn't make much sense.
"You will need two 27C256 EPROMs (or compatible 256Kbx8 EEPROMs) flashed with each of the split files, then place them in the correct sockets (U18 and U19, respectively)."
I live in the US (South Carolina), but would appreciate the help.