You should read the message from "ThisMayHelp" carefully again. What you need to do:
Fill 1040 and W-7 (you will need many certified documents) and file it together as instructed, there is a unique address (follow 1040 instruction). Fill in as TBD (to be decided) wherever an ITIN is needed in 1040.
Be sure to follow the instruction of W-7 VERY CAREFULLY.
Good luck!