North Miami (Fla.) Employees' Retirement System expects to issue an RFP by late April for an independent actuary to review the assumptions of Gabriel Roeder Smith, actuary and investment consultant for the $53 million general employees' and $22 million police officers' plans, said Carlos M. Perez, city finance director. The search was to begin in the fourth quarter, but more pressing city issues and staff changes in the city's purchasing department forced a delay, Mr. Perez said. A deadline for proposals has not been set, but once a firm is hired, the review is expected to take a month, he said. The plans use a 9% long-term expected rate of return. Trustees will not use a separate consultant.