Notwithstanding section 26 of chapter 22C of the General Laws, or any other general or special law to the contrary, Kerry McHugh, Dermot Moriarty, Richard Eubanks and Steven DelNegro, shall annually or retroactively be eligible to pay into the state retirement system a sum equal to the salary differential between the ranks of sergeant and lieutenant as each individual has already retired.  Within 30 days of the effective date of this act, the state retirement board shall inform the persons named of such eligibility.  Within 60 days of receipt by an individual of the notice of eligibility, an individual so informed shall notify the state retirement board in writing of the intent to pay said retirement differential and continue to pay any such differential from the date that each individual had retired in order to have their retirement calculated at the rate of lieutenant under this act.  The board shall annually calculate the amount owed together with any interest and upon a participating individual’s retirement shall pay said retiree at the level of a lieutenant.  The above individuals who have retired shall have their rank designation from the Department of State Police be amended to lieutenant as a result of two individuals who were promoted to lieutenant before them with lower examination scores on the lieutenant promotional examination.  The amended rank designation to lieutenant is for retirement purposes only.