Is that it for the entire file? If not, show something representative and expected output.
Assuming that is it, you need WHEN=GROUP for 'read' and PUSH the 1,2 for the count to an extension of the record, RECORDS=3. WHEN=GROUP for 'write', PUSH 1,2 to a different place. WHEN=(logical expression) for 'skip' and calculate with 1,2 and the two PUSHed values.
This is basically your code from the first CNTL file. To cut back down to 80-byte records, you could have used OUTREC BUILD, or OUTFIL BUILD or you can use IFOUTLEN (the most efficient way to do it) which sets the record-length to the value specified. I've cange your BUILD to OVERLAY, and included the RECORDS= I suggested (not particularly give you much for this task, but gets you used to what they can do).