Sonata Admin Bundle - Form type: sonata_type_collection - custom template?

Is it possible to override the template for the form type: "sonata_type_collection"?

Ive tried along these lines:

$formMapper->add('slides', 'sonata_type_collection', array(), array(
                'edit' => 'inline',
                'inline' => 'table',
                'sortable'  => 'priority',
                'template' => 'MyBundle:Form:slides.admin.html.twig'
            ));

but to no avail.

I know I could override the entire template, but I only want to do it for this form, not all the places where I use this form type.

Does anyone know if this is possible?

Thanks