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No matter the condition of your 1966 GTO, OPGI offers twenty-three Proportion Valve related parts to boost performance and get your 1966 GTO back on the road. Choose from trusted brands like CPP, Fine Lines and RESTOPARTS, with prices ranging from $3.85 to $115.99, all backed by our Price Match Guarantee. With OPGI’s 60-day return policy and thousands of verified reviews, you can shop confidently for your 1966 GTO restoration. Enjoy fast shipping directly to your home, or visit our Southern California Showroom & Warehouse to see our Proportion Valve related parts in person.
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