Here is a patch which converts the original mapper in Addams Family from MMC1 to MMC3.
Addams Family, The (USA).nes - NOINTRO
CRC32: 08E2AF80
MD5: 186023FD956CB560706817A96B7BDFA4
SHA-1: C831410A86A9B759A1E5EC53E8E1EE6789C79569
SHA-256: F1EA177A4B51CC4A08799AC17ED5ACE63F6E5701FEBDF310DFB891E6A77DA926