AFTER 1965? This is impossible. You can theoretically get Spain to vastly improve its economic importance post-1975, but its economy is simply not going to be larger than France's.
I don't know how a country can prepare for the upcoming oil crisis especially one lacking in native energy sources like Spain. Let's say that the Franco government was still concerned about the Spanish economy being able to be independent even though it had initiated reforms. As a result of far sighted leadership, the government enacted to have petroleum reserves (as well as other essential commodities were critical to Spanish growth) just in case. It then invested in an early form of energy efficiency to reduce the need of spending foreign currency on imported oil. It could then use the additional savings for investment in Spain. It also decided to increase power generation to be done through coal and nuclear for the same reason, thinking economic integration specifically with Europe would be better than the Arab oil. This substantially reduced the need for oil and provided a cushion once the oil crisis hit. Spain therefore weathered the crisis much better than OTL.
To compensate for this more mercantile policy, the Opus Dei technocratic reformers invested more in future value added industries. Besides becoming a source of automotive manufacture, chemicals, and textiles, electronics became important as well. The Spanish government also divested from its state owned enterprises at the height of their boom, allowing them to be further refined by market forces, and the used to proceeds for further investment in other areas. Importantly, Spain just doesn't establish industry, it modernizes the economy so that it avoids the need for reforms during the oil crisis that temporarily cripples growth for the decade following 1975.
As part of the transition planning, Franco accepted that some form of democratization was going to happen after his death, and that early entry into the EEC was essential. Or perhaps Franco had some kind of stroke, and the technocrats were able to take power from the hardline Francoists, perhaps using Juan Carlos as a figurehead. (I admit, this is a huge challenge for a realistic departure). Then when Franco dies, the democratic transition occurs much more smoothly, and because Spain is doing relatively better in the oil crisis than their economic competitors, the new government defers economic judgment to the same technocrats. Spain enters the EEC earlier - say 1980, benefits from development funds, and is able to take better advantage of EC market.
As a result, Spain continues to raise up in the economic rankings. However, I still don't think this causes it to bypass France in terms of GDP. Perhaps GDP per capita, but it'll be close.