Ultra 30 ?
You're in luck.
Sun gives complete free documentation for that model system in the Sun System Handbook.
You get to see what would otherwise be only visible with a service contract login to the SSH.
http://sunsolve.sun.com/handbook_pub/Systems/Example/U30.html
I suggest you start with setting the target ID to 6 and leave all other jumpers alone.
If it's not immediatly recognized at OBP when you probe the SCSI bus,
you can consider playing with the termination jumper.
Information for that drive is easily found at HP's web site.
http://h10025.www1.hp.com/ewfrf/wc/product?product=58737&lc=en&cc=us 8;dlc=en&submit.y=0&submit.x=0〈=en&cc=us
http://h10025.www1.hp.com/ewfrf/wc/document?docname=lpg41298&lc=en&cc=u s&dlc=en&product=58737〈=en
It should "just work".