Recommended procedure for precise placement of MICR Line using APY2021X1C template (Stub Over Check)

Our client will be using XMLP checks for production check printing.  XMLP setup documents provided by Oracle Support discusses MICR and Signature creation but does not address the need to precisely position a MICR line for Bank Check Reader requirements.  Posing this question to Oracle Support was not return answers to this question, which is why I am turning to the Oracle Support Community.  I have created a variety of multi-invoice checks, even one that incorporated an overflow stub.    I find that the delivered APY2021X1C template dynamically varies the stub length based on the number of vouchers paid, which does