How to crfeate a Paycyle file for Checks-Create a layout per bank requirements

Hi,

We already have a layout setup  for Check that is used to create paycycle file that is sent to the bank and they print the checks and mail them out. We are switiching banks and the new bank has different requirement for the format of the file. Where can this be changed?

Basically, when we run a paycycle, we get 2 files, one for ACH and one for CHK. Both files are sent to the bank. We need to change what goes on the CHK file. Where can this be changed