Switching from thin to thick Ethernet on a Sun 3/50

[Matthew Larson]

We have a Sun 3/50 that was running happily using thin ethernet.  Now we
would like to run it with thick ethernet.  We plugged in the drop cable
and -- nothing.  For the record, it is running SunOS 4.1.
Rumor has it that there is a jumper change required to effect this change.
Could some kind soul tell us how to do this?

Thanks very much,

Matt Larson                            "I believe in the fundamental
matt at ils.nwu.edu                        interconnectedness of all things"
NU Distributed Systems Services               - Dirk Gently