Under such rules and regulations as the retirement board may adopt and promulgate, a full-time or part-time employee of a city, village, fire protection district, or township who becomes a municipal county employee shall transfer all of his or her funds in the retirement system of the city, village, fire protection district, or township by paying to the Retirement System for Nebraska Counties from funds held by the retirement system of the city, village, fire protection district, or township an amount equal to one of the following: (1) If the retirement system of the city, village, fire protection district, or township maintains a defined benefit plan, an amount not to exceed the initial benefit transfer value as provided in section 13-2401, leaving no funds attributable to the transferred employee within the retirement system of the city, village, fire protection district, or township; or (2) if the retirement system of the city, village, fire protection district, or township maintains a defined contribution plan, an amount not to exceed the employee and employer accounts of the transferring employee plus earnings during the period of employment with the city, village, fire protection district, or township. The employee shall receive vesting credit for his or her years of service in a governmental plan, as defined in section 414(d) of the Internal Revenue Code, maintained by the city, village, fire protection district, or township. Payment shall be made within five years after employment begins with the receiving entity or prior to retirement, whichever comes first, and may be made through direct payment, installment payments, or an irrevocable payroll deduction authorization.