As John suggested, I think it would make more sense to send the proposed
standard (RFC 1876) Latitude/Longitude LOC record than to use some
esoteric ham-only thing like Maidenhead locaters. So what you'd do for
a site located at the coordinates 52°22'23"″North 4°53'32"″East
at an altitude of -2 meters is put this:
-L 'w1aw LOC 52 22 23.000 N 4 53 32.000 E -2.00m 0.00m 10000m 10m'
Note that many of those fields are optional; you could legitimately
put just
-L 'w1aw LOC 52 N 4 E -2'
See the wikipedia article
https://en.wikipedia.org/wiki/LOC_record
or the RFC for details.
I think this would make it much easier to plot a map point, and it has
the advantage that the data could be integrated into the DNS later.
- Brian