got the keys i need for trucha, after trying a few iso's tutorial does not show how to replace existing files to produce a boot dvd for VC games *** REPLACING FILES ON ISO *** This section assumes you now know how to navigate through Trucha Signer. 27. Create a backup copy of the ISO you want to edit. 28. Navigate to the file you want to replace. 29. Right-click on the file and select "Replace". 30. In the popup window, select a file that is EQUAL IN SIZE OR SMALLER.