This might help...
Code:
# shopkeeper, banker, beastlord gm, enchanter gm, magician gm
update `npc_types` set class=41 where class=32;
update `npc_types` set class=34 where class=31;
update `npc_types` set class=33 where class=30;
update `npc_types` set class=32 where class=29;
# wizard gm, necro gm, shaman gm, rogue gm, bard gm
update `npc_types` set class=31 where class=28;
update `npc_types` set class=30 where class=27;
update `npc_types` set class=29 where class=26;
update `npc_types` set class=28 where class=25;
update `npc_types` set class=27 where class=24;
# monk gm, druid gm, shadowknight gm, ranger gm, paladin gm
update `npc_types` set class=26 where class=23;
update `npc_types` set class=25 where class=22;
update `npc_types` set class=24 where class=21;
update `npc_types` set class=23 where class=20;
update `npc_types` set class=22 where class=19;
# cleric gm, warrior gm & banker
update `npc_types` set class=21 where class=18;
update `npc_types` set class=20 where class=17;
update `npc_types` set class=40 where class=16;