I've been searching various sources for a new fuel sending unit to fit my 64 Dodge Dart. Some pictures depict units with plastic floats and others brass floats. Any recommendations?

Shouldn't really matter. If all that's wrong with your original sender is the float's sunk, you can replace just the float — see here. There are three suppliers I'm aware of for this sender: You can get a new one from Chrysler (p/n 4051 004, about $86 thru www.chryslerpartsdirect.com ). You can get one from Spectra Premium, which is a Canadian outfit though I don't know where their senders are made. There's also a Chinese company making them out of stainless steel; there's a guy on eBay out of Wisconsin who sells those and I'm sure they come from other vendors, too.

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Too many people who were born on third base actually believe they've hit a triple.

Thanks Dan. The previous owner initially told me his mechanic was going to solder the current float, but instead simply replaced it. It was nice to have an operable fuel gauge during the long trip home yesterday. During the first leg of the trip, I thought the gauge was inoperable, but after about 25 miles, it dropped suddenly from F to 3/4 full. Seems it is hung up a bit. Not wanting to tempt fate, and at the same time getting some exercise, I simply gassed up every 200 miles. The lowest the fuel needle ever went was to the 1/4 full position, and the most fuel I could squeeze into the tank was 10 gallons.