Disable Product Type Sideboxes

[rbarbour]

I have created a new Product Type - The extra fields appear in drop down select sideboxes on my site.

I want to disable those sideboxes except when on pages of that product type.

Example - this new product type will have its own category, so I only want those sideboxes to appear in that category.

I have tried several if statements even
// test if box should display
if ($this_is_home_page) {
$show_custom_sidebox = false;
} else {
$show_custom_sidebox = true;
}

nothing seems to be working