Fixed length flat file to array with no delimiter

I have the following flat file:


Looking closely, you can see that there are three strings (1,2,3 - A,B,C - X,Y,Z). I want to put these into a document list as follows: DocumentList/Field1,Field2,Field3. The file will be fixed length, and always have three values for each array. The fields are also fixed position, so 0-10 will be field 1, 10-20 will be field 2, 20-30 field 3, then 30-40 field a of the second item in the list.

Can I make make this happen using WmFlatFile, or do I need to create the array after getting the data from the flat file.

I think once you have parsed the fixedlengh data then build the array this would be ideal way and can wrap accordingly in the doclist.