Excluded site header still showing

So would I need to add a new snippet for each category?

No. You just need to alter the Conditional statement a bit.

You can try replacing this in the code:

is_tax( 'category', '180' )

with this:

is_tax( 'category', array('180', '182') )

Ok,
Thank you.
I am going to try but have some other tasks I need to do as well so cannot stay on this.
I am going to check some of the settings in Directories Pro as the category is not showing correctly.

Many thanks for all your help, really appreciated.

You're welcome, Robert! Hope it goes well!