IDOC to File using content conversion

Hi,

Is it possible to mention start and end position in the output file using content conversion or it can be done using message mapping in PI 7.1?

eg:

standard length for first field = 10. and passed value = "NEW_S" , output should be  "NEWS_S     "

standard length for second field = 20. and passed value = "12345678" , output should be "12345678           "

standard length for third field = 5. and passed value = "PC", output should be "PC   "         

Final output as per below screen shot, it should be

(NEWS_S     12345678            PC   )

Please guide.

Thanks & Regards,

Vinoth