Hi Apple,
Thanks for the instructions.
I couldn’t figure out how to read the file into a variable Set Value so created an extension to get the contents and return it as a string (based on this - Server Side Read & Write File - but converted to node.js).
Then worked through your steps but then couldn’t get the CSV Parse step to use the string, it wants a file.
Then in my testing I eventually figured that since I didn’t need the lines at all I could just remove them.
I changed my custom extension to read the file contents, remove the offending lines and save it back in place so then the CSV parsing works.
Not really in the spirit of no code but works in my specific case. 
Also, trying and failing is my preferred method of learning so this exercise was totally worth it.
Thanks Paul.