You basically have it correct.

On Schedule 1 of the 1040 - Other Income - list the foreign income items and the U.S. dollar amount. On the next line list US-INDIA TAX TREATY - ARTICLE XX EXEMPTION and then subtract out the proper amount. Some country exemptions are 100%, others are 10%, 90%, etc.

Then prepare Schedule OI to attach to the 1040 as a .pdf attachment (OTHER). On Line L(1) list each exemption with the amounts that match the 1040.