Depending on the nature of the law enforcement position, you may still have to disclose the record. See Section 943.0585(4), Florida Statutes. Additionally, certain enumerated offenses are ineligible for a sealing and/or expunction.
There is a specific provisions that deals with retention of criminal history records of minors. Depending on the offense, the records will be expunged at age 24, unless an exception applies (section 943.0515, Florida Statutes).
In order to better clarify the answer, you would need to discuss with a lawyer what types of offenses you were charged with.