I figured it out. Had to hack out some code from wp-comments, modify it accordingly (add globals, tweak parms, insert HTML, etc), and put it in the posts.html file — plus I had to empty the comments.html file too (except for one line dummy line — can’t be totatlly empty) so that comments didn’t show up twice when viewing posts. Also had to modify the post form, strip out Smarty and put in PHP code.
Works now. Woooohoo!