AT&T 3B2 300

Does anyone here have experience with AT&T 3B2 300 hardware/software? I apparently have a pile of doc and software which is in complete disarray. The software is all on 5.25" DSDD diskettes, and i'm not even sure if i have what i need to format and reinstall an operating system. Does anyone know what type of hard drives these computers support, or know if the floppy drive can be upgraded to high density? I have two base systems, one has either been cannibalized, or merely every screw has been removed, since everything from the power supply to the floppy drive is floating free in the case ;) The other unit appears to be in much better shape. The student chapter of ACM at the university here had these, so you can imagine what sacrelige may have been comitted... -Lawrence LeMay lemay(a)cs.umn.edu