This is how I did it, if it helps
Download and fill I-131 forms. I requested expedite service, as i needed to be back in Japan in a hurry. I wrote a cover letter stating my request and reason. Add the money order (305$ for re entry permit, 80$ for biometry) I included a pre paid express mailer too. Outside the envelope type "Re entry permit- expedite service" in clear letters.
I was called for the biometry after 3weeks and got my permit the next week.
If you need more information, I'd be happy to.