1957 Star Chief fuel sender
 

I purchased off ebay a NOS fuel sender which the seller listed as for a 1957 Pontiac Star Chief, pictured here with a 5/16" outlet pipe and a brass float:-

https://www.trifive.com/forums/pictu...ictureid=79942

Today I pulled the fuel tank to replace the sender, but the one that came out of it was the same as this one (which is also listed on ebay for a '57 Pontiac) with a 3/8" outlet pipe with a oblong plastic float.:-

https://www.trifive.com/forums/pictu...ictureid=79940

The outlet pipes are also at different angles (and different diameters as above) which makes them not easily interchangeable. As I can't be sure that the one I pulled out is original, can anybody with '57 Pontiac knowledge tell me which one is the correct sender unit please. If the ebay one is not in fact for a '57 Pontiac, then I will try and return it.

Any help would be much appreciated.

Mystery now solved. The supposed '57 Pontiac sender was in fact one for a '57 Chevy, so the seller had mislabeled it. Have now sold it on to a Chev owner, and had my old unit repaired, which was leaking where the solder had cracked.