Brahm - Ok, I was able to check out the TWTCommish's shoutbox and get it to work with myvbindex. Just install the hack exactly as you normally would, except at the part where it tells you to place the code in your forums index.php, instead place it at the bottom of your myvbindex.php file right above:
$getbgrow=getrowcolor();
eval("dooutput(\"".gettemplate('index')."\");");
Also be sure to leave out the bottom part where it has:
eval("dooutput(\"".gettemplate('forumhome')."\");" );
Then you would replace the content of the forumhome_shoutbox template with the content in the text file attached.
You will probably want to also edit your shoutbox_postshout template and remove the / before shoutbox.php on the 3rd line so the form will be pointing to the right place.
That should be it.