Filing officers with whom notices of federal tax liens, certificates, and notices affecting such liens have been filed on or before July 1, 1967, shall, after that date, continue to maintain a file labeled "federal tax lien notices filed prior to July 1, 1967", containing notices and certificates filed in numerical order of receipt. If a notice of lien was filed on or before July 1, 1967, any certificate or notice affecting the lien shall be filed in the same office.
§ 71-3-207, MCA