Be aware of what you are buying, most ebay sellers haven't a single clue what parts fit.
For example, cars use a different Y block water pump than the trucks.
1954 truck 239/256 Y block pump (EAT-8501-B) is 1954 only. 1955 239/256 pump (B6T-8501-B) is the same as 1956 272 H/D.
1957/61 272/292 C Series Tilt Cabs use a specific water pump (B7T-8501-A).
B6C-8501-B .. Y Block Water Pump / Obsolete
1956/60 F100/600 272 M/D / 1957/64 F100/700 292 / 1962/64 292 C Series Tilt Cabs.