Hi Tom, and all... That is one-mail that I would rather have not seen dug up, as it really muddies the waters. The correct dish-type core plug size for the 413 blocks up to and including 1961 is 1 5/8". That is what the parts books call for. 1 41/64" plugs are not ever mentioned in any parts books. I don't even think that size plug was ever made, either by Mopar, or Dorman, or other suppliers. My recollection of subsequent conversations with George Riehl on this matter is that we finally came to the conclusion stated above - and I felt it necessary to post this reply publicly before everyone gets confused, and runs out trying to buy 1 41/64" core plugs ! John Hertog Sag Harbor NY ------------------------ Yahoo! Groups Sponsor --------------------~--> Yahoo! Autos. Everything you need to know about buying or selling a car. FREE Quotes, 360° Tours, Research, Blue Book, Compare Vehicles, Buy Used http://us.click.yahoo.com/kEZsdA/bwnGAA/YiGOAA/8LmulB/TM --------------------------------------------------------------------~-> To send a message to this group, send an email to: Chrysler300@xxxxxxxxxxxxxxx For list server instructions, go to http://www.chrysler300club.com/yahoolist/inst.htm Yahoo! Groups Links <*> To visit your group on the web, go to: http://groups.yahoo.com/group/Chrysler300/ <*> To unsubscribe from this group, send an email to: Chrysler300-unsubscribe@xxxxxxxxxxxxxxx <*> Your use of Yahoo! Groups is subject to: http://docs.yahoo.com/info/terms/