I thought I had a 235 six cylinder in my 1955 2nd seies 6400 truck but while reading the old post on the forum I came across some literature that said there were some 261 engines in the bigger trucks and it listed the block number for the 1955, 261 as 3837012. When I check, that is the number on my block. Also it looks like under the orange paint on the engine it used to ne painted yellow.

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