[MarkFL]

What I would do is create a plugin hooked at "postbit_display_complete" with the code:

PHP Code:

if (in_array($forum['forumid'], array(421,578,680,638,597,36,246,247,490,250,531,748,742,740,744,129,769,772,770,771,691,711,712,713,714,715,716,696,717,718,719,750,751,752,753,754,779,720,778,721,722,723,763,767,764,765,776,777)))
{
    $post['signature'] = '';
} 


The advantage to using a plugin vs. a template edit is that it will work for all styles and will work whether you use "postbit" or "postbit_legacy" and it can easily be enabled/disabled.