[Vwdiesel] Glow Plug Newbie

[Kneale Brownson]

A lot of patience, a little skin loss and I have the nonfunctioning glow plugs out of my 1994 Jetta TD.  The third from the front came out with the greatest muscle requirement, the second with the greatest challenge, the front with the most patience and the fourth was a breeze.   The ends all had a fair amount of carbon on them, and the threads of #3 and #4 had carbon on them.  Three & 4 reminded me of sooty spark plugs in some gassers.
   
  Here they are, L to R = 1 to 4:  http://www.pbase.com/kneale_brownson/image/98180657/large
   
  Should the new ones go in with some antiseize on them?
   
  Is the soot indicative of some other problem?