Hi Mr Patel,
The scenario you have given involves following transactions:-
i) Letter of Credit Issued by State bank of India
ii) Vendor Submitted document for payment " Document Under LC".
iii) To make payment for the "Document presented under LC". SBI arranged from Buyer credit from Bank of America. It means you have to create Bank of America as a Business Partner under Counterparty role and State Bank of India as a gurantor role.