Elegant way to map UID's and GID's on dump/restore?

[John]

I have some GID's and UID's on my system that date back to FreeBSD
0.9.  No, actually, they date back to my NSC 32016-based GENIX
system, come to think of it, which predates all FreeBSD. (Really
cool architecture - highly orthongonal - very VAX-line - totally
unlike the IA32 "native mode" stuff - 2Mhz and 256K of RAM. :)
Anyway - enough reminiscing...

On my next system roll forward, I would like to remap these into
the new conventions and standards for GID's and UID's, and I imagine
I'll do that with various "find" and "chown" commands, but if someone
knows of a more elegant way to remap these in the dump/restore process,
I'd love to know about it.

Thanks!
-- 

John Lind
john at starfire.MN.ORG