Adding my two cents worth, this task is really not as simple as it appears, the complexity also depends on what the TS meant by 'File*', for instance:
a. Are the datasets (or 'File*') in question, of fixed length or variable?
b. What is the length in question?
c. Is the data only AND ONLY a '2 byte number'?
d. Is the mapping of data between the two datasets always going to be one-to-one, i.e. 1st record from DS-1 needs to be appended to 1st record of DS-2, and so on?
e. Then there is also the part about the number of records in both the datasets, will it always be same (i.e. 1 record each) or there is a possibility of different count?
If I have to go purely by what the TS has posted, i.e. "File 1 and File 2 with one record as count 05 04 respectively and I would like append it into single row", then assuming that the data is stored in a QSAM dataset, a simple method would be to DD concatenate the two QSAM DS and use ICETOOL RESIZE operator.