I don't know that you have a choice
I think you have Bosch from the dealer or Bosch from a 2nd source
rockauto lists them for ~$32.
http://www.rockauto.com/catalog/raframecatalog.php
note -they are very sensitive and you can't really tell if they're good before installing them- check some of Ranger1's posts - but dropping even a couple of inches, contaimination ect - will kill them.
resistance spec is .5 to 1.5 ohms. (my good ones were 0.7 and bad is ~120)
oh and #3 is probably measured from the back i.e. it's the 2nd from the front - measure resisitance - pull plug and remeasure to confirm.
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2005 CRD
stuffSkeptic quod gratis asseritur, gratis negatur