Doubt regarding sender file content conversion

Hi Experts

This is my source XML structure, how to define Sender file adapter (Content Conversion) and filed lenths: COMMIT_I 1, STUDENT 12, ID_TYPE 6, ID_NUMBER 60, VALID_FROM 8,VALID_TO 8

<?xml version="1.0" encoding="UTF-8"?>

passhe.com/UpdateIdNumberISA32">

<COMMIT_I>X</COMMIT_I>

<IDENTIFICATION>

<STUDENT>Student</STUDENT>

<ID_TYPE>New</ID_TYPE>

<ID_NUMBER>12345</ID_NUMBER>

<VALID_FROM>12/03/2008</VALID_FROM>

<VALID_TO>13/04/2008</VALID_TO>

</IDENTIFICATION>

</ns0:IDENTIFICATION_ADD_Req_MT>

Please suggest me how to configure Sender file content conversion

Thanks

Dhanush.