[kpmedia]

Ah-ha, now that works (showthread_complete, using $thread[captitle] in SHOWTHREAD, and the aforementioned plugin).

But there's still one more step I'd like to take now, if possible...

I use this plugin for new posts, to run ucwords() on all but specific stop words in an array:

$smallwords = array( 'of','a','the','and','an','or',
'nor','but','is','if','then','else','when', 'at','from',
'by','on','for','in','to','into','with' );

$words = explode(' ', $vbulletin->GPC['subject']);

foreach ($words as $key => $word) {
    if (!$key or !in_array($word, $smallwords)) $words[$key] = ucwords(strtolower($word));
 }

at newthread_post_start

It works great and all, but it does nothing for old posts.
Right now, I have text-transform:capitalize; CSS in some of the templates, to "fix" terrible capitalization by members. But it caps everything, including stop words (a, and, the, or, etc). It also did nothing for the HTML page titles, hence the need for this plugin.

I want to adjust the plugin now so that it doesn't capitalize stop words like the CSS does.

The new post plugin above does what it should, but I'm thinking there's a way to copy some of that functionality (with new variables, of course) and merge it with $thread[captitle]

But I'm not entirely clear on what should be removed/replaced. Any ideas?

Again, I really appreciate your replies thus far.