Search Custom Field Select All

I have set up a custom field search “make” in advanced search. The use a select box to drop down to a popular list of makes (of tractors for example).

I would like to have an — All Makes — option at the top. With the Category Country and State search boxes they all start with a blank and then the dropdown list appears. But with my custom field the first vale always appears. If I leave a blank line at the top then that is fine until someone actually selects one the the drop down options — then the blank disappears and the first option becomes the default.

Can I set this up so that it works the same as the others – or at least has an — All Makes — as the first line that will return all values.

Ideally I would it to populate the select list with only those makes for which I actually have listings.

I see Mark hint to use Syntax value[text] but I really don’t get that. Have tried google but everything that I find relates to writing PHP code. Maybe a link to something that would help me would be fine.

Thanks

Mal

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