Those 71 valves are famous for leaking. Had friends buy NOS ones and they started leaking. If you don't care about being correct you might consider using a 70 and up A body valve. Easier and cheaper to fine. Last a long time.
StratOvent cars use a different expensive valve so use the A body valve.

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72 Satellite Sebring Plus 440, 72 Dart 5.9 4-spd, 68 Valiant, 73 W200, 78 D100 sb, 78 D200, 98 DAKOTA, .
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