My ARC is with a company in Taipei where I do overseas marketing. My question is, I would like to take a part time job teaching or editing. Is it possible to get a second work permit with this type ARC?
Teaching, yes; editing, maybe. The latter, if through an office or non-school location, needs a different kind of work permit and depends on a different system. If you work full time with the marketing company, there is a good chance you won’ be able to get a second office job. (This needs to be confirmed, though, through the proper Executive Yuan.)
Detailed information on the teaching work permits is on tealit.com.
You’ll also need a letter or statement from your current employer (who primarily supports your ARC) saying they are fine with you getting this second job.