> I would add that there should be a distributed SPARC kernel that mimics
> the sun4c's 3 <-> 0 swap (bizarre though it is).

Uh ... there is.  Read the NetBSD/SPARC 1.1 INSTALL document:

	To ease the installation process, the default NetBSD kernel in the
	distribution is setup to match the Sun mapping above by hard-wiring
	scsi-id#3 to sd0 and scsi-id#0 to sd3.  The remaining drives will be
	dynamically mapped to other sd* numbers.

The sun4c's id. 3 -> sd0 swap is not so bizarre when you know the story.

When the SPARCstation 1 first came out, the most extant external peripheral
which people would be likely to want to move over from their legacy Sun-3
desktops was the "shoebox".  This contained either one disk, two disks, or
one disk and a QIC-24 1/4" tape drive.  The disks in that box were always
numbered "0" and "1" and the id's were *NOT* easy to change (no pushpin
outboard mechanism).  Rather than conflict with these cast-in-stone disks,
the default for the new systems was made "3" instead.