How to populate Arist & Title tag with info from title tag

I asked this question awhile back but left out some pieces so wanted to ask it again.

I've got 100+ compilations that have the following File names and Title formatting.

File Name: 01 - Bob Marley - Natty Dread.flac
Title: Bob Marley / Natty Dread

Title: Natty Dread
Artist: Bob Marley

What I would like to accomplish is getting the artist tag populated and the title tag cleared of the artist name and the /. I've tried several methods without any success. I hope I am explaining myself well.

Any ideas?

Create ana action of the type "Guess values" (or Import tag field) for %TITLE%
Enter as mask:
%artist% / %title%