Success! I soaked the bowl in gasoline overnight followed by soaking in lacquer thinner for a few hours more. That removed some, not all, of the old gasoline deposits. I filed two slots into the inner sidewalls of the stuck pump piston with a needle file in order for a flat-bladed screwdriver to have something to grip onto. The real breakthrough came after the application of heat from an electric heat gun on the highest temperature setting applied to the frozen part for about a minute. A few turns of the screwdriver and it was out. What a relief! I hope that the rest of the rebuild is uneventful.

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