Spilhaus Space Clock and Southern Hemisphere star chart

I hope this is the right place to ask this question. It has to do with
calculating a curve that shows the sun and moon rise in the Southern
Hemisphere

I fix Spilhaus Space clocks for a hobby. I recently fixed one and sent
it off to South Africa. The day after I sent it, it suddenly occurred
to me that the star chart was for the Northern Hemisphere and the clock
would not be of much help to the new owner!

The Spilhaus Space clock provides a wealth of "timely" information
including the time, positions of the sun and moon, tide information, and
a rotating star chart. You can find out more about the clock and the
specific problem here:

http://www.sandsmuseum.com/restoration/starchart/

The clock consists of a series of transparent discs that each have some
information on them. The last disc has the star chart and rotates
approximately once a day. There is a stationary disc in front that
shows the horizon.

At first, I thought I could just print out a star chart for the Southern
Hemisphere and fix it on top of the existing Northern Hemisphere disc.
However there is some additional information on the disc that includes
sunrise and moonrise information and an X centered at the north star
with degree markings. The disc also has the months arranged on the
outer edge.

I think I can figure out how to print a Southern star chart and position
it correctly relative to the months. But I do not know what to do with
the sun and moon rise lines and the white X with degrees. In my mind, I
reverse East and West when I go South, but I do not know if the rise
times are different. I can figure a way of taking the lines and
superimposing them on top of the chart. But I do not understand the
phase or if the lines need to be mirrored.

I would appreciate any help or suggestions,

Michael
The Sands Mechanical Museum
www.sandsmuseum.comm
.

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