(a) Any other provisions of law to the contrary notwithstanding, no creditable service of any nature which may be allowed under Code Section 47-2-93 or subsection (b) of Code Section 47-2-96 shall be used in any manner to qualify a member for involuntary separation benefits.

(b) No credit shall be given under Code Section 47-2-93 except for full-time state employment; provided, however, that service after January 1, 1954, as a tax collector, tax receiver, or tax commissioner or as an employee of any such tax official shall be deemed to be full-time state employment for the purposes of this retirement system and any service as a tax commissioner, tax receiver, or tax collector or any employee of such tax officials after January 1, 1954, to the date any such official or employee became a member of the retirement system shall be credited as membership service credit upon payment into the retirement system before January 1, 1977, the employer and employee contributions, plus regular interest thereon, for such service.