Become an Expert Excrement Expeditor

Become an Expert Excrement Expeditor is an unmarked quest in Fallout 2.

Detailed walkthrough
Talk to Bill, who is the caravan master of Broken Hills in 2241. He can be found in Broken Hills Downtown area, south west building. If you shovel brahmin dung for him five days in a row, you'll be paid a tidy sum of $500, 500 XP and get the Expert Excrement Expeditor perk, which increases your Speech by 5%. Your Broken Hills reputation will take a slight hit, though. Once you achieve the perk, however, Bill stops offering the opportunity to shovel dung.

Bugs
With low Intelligence, one can only talk to Bill before having taken up any jobs despite the code and lines for a low-intelligence character otherwise being present for all the 5 iterations and for after they have the perk.