I am very late replying to this topic but I would strongly suggest NOT using RockAuto for any parts especially considering you're outside the USA.
Some here will perhaps addresses or contact information for more reputable and knowledgeable companies.
If you're able to translate your request into English the website Ford Truck Enthusiasts would be a very good site to investigate. Most notably member Mark Kovalsky would probably have fantastic recommendation about a possible reliable tutorial. He or others in the Transmission sub-forum with experience with self-repair of your particular transmission may have a number of vendors they would recommend.
Those members there would probably also have reliable vendors for complete ready-to-install rebuilt transmissions too but the cost of transportation would be extremely costly I'm sure.
Use this link for a quick investigation and maybe it will be useful to you: www.ford-trucks.com/forums/forum69/
IF you would need help securing and shipping any parts you'd buy from the USA I would be willing to help in any way possible. Please know I am NOT skilled or experienced with transmission repair, just happy to help if I can in any other way.