Just use paper you can check back fill up carefully and submit also each evidence ie: your wedding photo, marriage certificate, etc and all of it mail it using priority mail with receipt sign provide by USPS it should be no problem. I have done it with petition for my wife and never got lost in the mail, Good luck man! Just also be put in mind CR1 process could take bet 18 month-24 months because every case is varies.Also if your marriage certificate and all the paper work not in English make sure you translate that approved by US embassy in Bangkok because that where the interview will take place for your wife later on.