[ By Howard Haykin] Credit Suisse Group, the 3rd-biggest M&A adviser this year, has a new co-head of the investment-banking group for financial institutions in the Americas.  In an internal memo, the firm named Craig Stine, 52, to succeed Steven Pierson, who will become a vice chairman focusing on client relationships.  In his new role, Mr. Stine will work alongside Neil Carragher. The group’s global heads, Alejandro Przygoda and Ewen Stevenson, said the financial institutions group “continues to be a vital part” of the investment-banking division. Stine, whose clients have included American Express and Capital One Financial, joined Credit Suisse in 2011, after leading Citadel LLC’s investment-banking effort. On a separate note, Credit Suisse said on Thursday that Boon Sim, M&A global head, is leaving to join Temasek Holdings Pte., Singapore’s state-owned investment company.  He’ll be replaced by Scott Lindsay.   [Bloomberg, 5/17/12]