Best Years for the 318 LA?

My favorite 318 is low mileage 72-74 mound road engine. Always well built and take a hammering. Look for this decal on the valve cover. But Now remember I am old .
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Wonder what that actually meant? Another mopar mystery. I'm beginning to think the entire mopar division was run while being high on acid. Hence the trippy info. Weird build codes. Fun colors. Lol. You name it. They did it.