Change showthread by showthread_2 in some forums

[chicote]

I am creating a product that depending on the forum he changes the Showthread, ah I would like to know, how do I get in the forum that I've chosen, instead of Showthread he shows a template Showthread_2?

Someone could give me a tip for that plugin, I created a plugin with the following code:

PHP Code:

if ($this->forum['forumnumber'])
{
$vbulletin->templatecache['showthread'] = $vbulletin->templatecache['showthread_2'];
} 


But is not working, I could fix that indicate how plugin, recalling that forumnumber is an option that I created empowered the manager of forums, to define which will use the forum shothread_2;

If I can help.