I don't understand your description. Are file1 and file2 separate input files or separate output files or ? Are you trying to create file1 and file2 as separate output files and then concatenate them as output file3? Why? Why not just create them as output file3 in the first place?
Please show an example of the records in the input file, or in each input file, and the expected output file or files. Show relevant values in the records for the effective date field and ABC field. Give the RECFM and LRECL of the files.
As for the position, length and format of the fields:
I think you're saying that the effective date field starts in position 20, has a length of 10 and is character format (C'MM-DD-YYYY') - right?
I think you're saying that the ABC fields starts in position 32, has a length of 1 and is character format - right?