Well, I don't know what to tell you. Obviously there is a limit as to how much they will put in the drop down bar. Probably to make it fit for people on lower resolutions. There might be an extension out there that solves your issue but I don't know of one off hand. I guess you'll just have to memorize the letters of the search engines you've defined. Maybe preface them with a letter and a number. Like, if you have three search engines you use to find subtitles you could label them 's1', s2' and 's3', or something like that.
Appreciate the kind input, in fact I DID find an extension::
"I ended up adding the "Search Center" extension, which does exactly what I want in as many search pages I define for it."