alter_pdl
hook, which get's whatever layout the system has decided for you in the layout
key in the array it receives. You could just replace that with the content of the pdl file you want to use. This will be the pdl that is passed to Comanche.load_pdl
hook. Hook::register('load_pdl', 'addon/custompage/custompage.php', 'custompage_load_pdl');