Help me sort my combo

Spark plug problems! Before I was running Champions and 1 matched Autolite for space considerations on the steering box. Shop tuned it with NGKs, which are too long for the space. I called NGK today and they said they don't have a shorter plug with the same rating so I'm hoping somebody can recommend a shorter plug to fit thats the same range. Any help is appreciated. R5671a-7 is whats in there now.

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