> What units are the coordinates in, and what is your source for them?
X and Y coordinates are from this website : [url=http://www.swgalaxymap.com/]http://www.swgalaxymap.com/[/url] (the author measured them from essential atlas or got them from other canon sources), Z is extrapolated from system/object descriptions (some systems are said above or under the galactic plane.)
The easy part is to transform X, Y and Z "atlas" coordinates into light year ones with Star Wars Galaxy center as reference.
Then compute some rotation to have coordinates computed from a parallel plane to the ecliptic.
And now you can calculate distance, RA and DEC.
I simplified it by having star wars galaxy center in front of Sun's North pole and face oriented to get rid of rotations.
> The current locations of star systems in CatalogsSW aren't really accurate or canon,
> and anyway Space Engine has limitations to the precision of RA and Dec coordinates
> in a galaxy 1.25 billion light years from the Sun.
Well it seems Star Wars Galaxy from CatalogsSW is too much far, far away
to accurately locate systems.
We might need to move it closer.
As a teaser here are some of the Old Republic ships I listed :