I had tried looking online for a decent map of the hiking trails on Mudeungsan in Gwangju, but had no luck at all, so I swung by the Park office whilst hiking up to Gyubongamsa yesterday and they gave me this very detailed map. I've scanned it in so others can use it aswell. You should be able to download a large version (2000 x 2753) of it from my flickr account. I hope it's useful for you.
NB: North is on the LEFT side of the map. The top of the map is east. I don't know why!