How do you add extra per-forum setting fields?

[Cars2007]

I would like to add a couple of per-forum settings that can be modified in the forum editor. I've already added the fields to the forum table. I know you have to hook forumadmin_edit_form to do this, but I'm not sure how to wire it up so that it actually loads & saves the fields from/to the forum table.

I also don't know how to get the field to show up in the $foruminfo array. I am looking at forumdisplay.php and seeing an array called $foruminfo, but when I print the contents of the array (print_r) I see a whole lot of fields - but not the two I added to the database. I looked up the datamanager documentation, and added this to the forumdata_start hook:

$this->validfields['thread_title_open_tag'] = array(TYPE_NOTRIM, REQ_NO);
$this->validfields['thread_title_close_tag'] = array(TYPE_NOTRIM, REQ_NO);

Yet, print_r-ing the $foruminfo array reveals the fields are NOT showing up.

I've spent a good deal of time searching for this info, and I've found a few useful pieces of information, but feel like there must be some kind of "starting point" that I'm missing. Is there some kind of walkthrough for doing all this? Otherwise, help on the above would be greatly appreciated.