1971 P10 leaky Rochester Monojet Carburetor

[71shortygray]

Have a '71 P10 shorty step van. Has been running fine. Started it up yesterday and started fine but wouldn't idle -- notice it was leaking fuel out of the bottom of the filter nut where the fuel line meets the carburetor. Tightened it up a bit but that didn't help. Took it off and visually the gasket, threads and filter look fine. Should I just replace the nut, filter and gasket or could this leak be an indication of something more complicated in the carb itself?

The carb was rebuilt a little over a year ago.

See image attached.

Thanks in advance for any help!