>now - I'll keep digging, I can't seem to find out what these mean :
>
>boot scsi-int/sd@4:0
>              ^^^^^^

In OF if you type `devalias' you'll see a list of devices.  scsi-int
will point to some hardware that is in your computer.  The sd@4:0 means
scsi disk with scsi ID 4 and the 0 is the first bootable partition. The
questions are:

1) Is NetBSD on a scsi disk (I don't know what hardware is in the 7600)?
2) Is the hard disk internal?
3) What is the scsi ID of the disk with NetBSD?
4) Is the NetBSD kernel on the first partition of the disk?

Something like

boot scsi-int/sd@#:0 

should work, where #=scsi ID, but your firmware could be broken (again I don't
know about the hardware in the 7600). 

Aaron Jackson