Change of Client and Location after H1B Petition Approval

We are a group of people working in Top Company from India. Our Petitions have been approved and now there is change of client and location before we go for 1st time Stamping. What are necessary process and documentation we need to take care of when we go for Stamping for a client other than the one approved in petition.
Our Employer is just Providing New Client Letter and New LCA of client location. Wanted to know apart from this do we need to do anything specific.
If Anyone is in such situation please let us know about the process we need to follow. Appreciate your help on this