Need some help with column handling

[Eric Lilja]

Hello, I just got back to emacs after a long absence. When I'm in 
latex-mode, I want to have the following settings:
Column number 72 should have a different color than the other columns.
Text should automatically wrap at the 76th column.
I tried this in my .emacs:
(defun my-latex-hook ()
  (message "Running my-latex-hook")
  (setq-default fill-column 76)
  (setq auto-fill-mode 1)
  ;; TODO: Highlight column 72!
)
(add-hook 'tex-mode-hook 'my-latex-hook)

But, I don't seem to get an automatic wrap at the 76th column and I 
don't know how to "highlight" the 72th column. The hook is executed, 
however.

How do I do what I want?

I'm using: GNU Emacs 24.0.50.1 (i386-mingw-nt6.1.7600) of 2010-06-14 on 
3249CTO
under Windows 7 Professional (64-bit)

Thanks!

- EL