Those 68000s were before my time. First SGIs I got to play with were MIPS machines. IRIX screwed me up for a long time.
Never got to play with one myself either, although we had one in storage for a bizarre reason. The relevant academics had this license for a package that would normally cost telephone numbers; the license was legally valid as long as this 68000-based machine physically existed, even though the software itself ran on other machines.
Never had that much of a problem with IRIX myself; at least once I caught on to the trick of installing it as minimally as possible and attaching an external hard disk with all the files from the full CD set copied to it. Mind you the collection of workstations that I got lumbered with took a couple of years to untangle and make sane.