Access Sage 50 through SDK with less privilege account

Hi,
 I am developing a .NET application to read customer and Receipt details from Sage 50 to import to our Microsoft Dyanmics CRM. Therefore I use Sage 50 SDK to connect to the company and access data via the API. However there are other sensitive data(Salaries, and other financial data) in SAGE 50, which my application should not have access. In that case how can I access the system with a less privilege account (Have read access to Customers and Receipts)? 
Thanks
Regards
Hiran