I don't know about the rest of it (the sort of mess you describe is one
reason I avoid using i386 boxen when possible), but....

> 3. What about getting disklabel(8) to ignore the fact that I'm trying
>    to force a label which I know doesn't comply with what it thinks?

I don't know of any way to do this with disklabel.  But I wrote a tool
called bsdlabel for manipulating BSD disklabels, even when they're
stored in files rather than disks, or when on an OS that doesn't
actually use them (older NetBSDs, or other UNIX variants).  It does a
few consistency checks, but they produce only warnings; it's very much
in the YAFIYGI mold.

I'll be happy to mail you a copy if you want.  (I'll actually be happy
to mail anyone else a copy if desired, too. :-)

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