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Battery Info

13xW-4-11/16xH-8-1/4. A Miata-Westco battery Part #12V31M may fit as well.

Type 24 fits later years and possibly early as well.\\ Dimensions on the 24 are L-10-1/4xW-6-13/16xH-8-7/8
Optima Red 75/35, Model 12853-fits but tightly
Optima Yellow-Top 51R

I am sure there are other options.