[Koha] edit record subfield before import to koha

Hello people, does anyone here dominate Marcedit well? I'm having a little problem here, if you could help me, thank you very much. when doing the iso conversion to mark with marcedit, my author field was divided by (^) and it looked like this: =100 Brito$bPedro Quelhas now I'm trying to get the $b to put a comma. I want to do the reverse with the publisher field that has no subfields to put subfields $a $b $c. =260 Alfragide: Dom Quixote, 2012. How do you explain? Ana Bela