DELPHI (the former AC DELCO) has stoppped manufacturing even numbered plugs. If you go to your parts guy and ask for an AC$44 it will cross to AC45. If you have an old parts store in your area, go see if they have any 44's on the shelf and buy them. A recent check on E-bay for AC44 shows that they are selling for about $40.00 for 8 of them. Also a AC Delco rapid fire #7 is the same as an AC44 (I think, maybe AC45Z I have good luck with them. I do not recommend Champion.
As John Sawruk (retired Pontiac enginer) stated at a convention I attended 2 weeks ago. AC DELCO plugs were enginnered for GM vehicles and nothing works better in them.

Just my 2 cents on the topic

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1940 Chevy G506 4112 cargo dump
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