That's when it gets a little hectic.
"There's not much to it besides the noise," Wilson said. "There's a lot of noise in here and it's hard to hear."
Four guys are usually inside the scoreboard, which resembles a shed. It's dim and a little dusty, understandable for a structure built in 1937 that has reached landmark status. Hundreds of steel plates labeled with numbers are littered throughout the separate floors.
And when it's hot outside -- like the forecast of 90 degrees for Tuesday's game -- it's even hotter in the scoreboard.
"If the wind's blowing in, you get nothing. When it's out, you get a nice breeze coming through here," Wilson said. "But when it's 90, 95, it's like 110 in here. This place is so hot, you can barely function."
There's also no bathroom, and with the constant action of the Cubs' game and others, no time to climb down the ladder to use the facilities.
As for the job, the crowd noise can make it difficult for others to hear Wilson call out the scores. Add in the popping of targets -- the white dots that make up the batter's number, outs, balls and strikes, and is operated by Rick Fuhs in the press box -- and there's always something making a racket.
"If these scores were coming up, I'd be screaming at the top of my lungs to the guys on the first floor," Wilson said. "With all this crowd noise and everything going on, they won't even hear me half the time, so I have to say it over and over again."
Everyone has a chart that shows where each game is on the scoreboard, which is how Wilson references changes -- yelling "bottom game" or "top game." The scoreboard can only fit 24 teams, so not all games are represented. The standings or rivalries usually decide which games are shown.
Wilson monitors the games and updates one side of the scoreboard. Another works the other side, while two others work the Cubs' game, so at least one set of eyes is always on the action.
The basic process of the hand-operated scoreboard has remained the same since the scoreboard debuted. The biggest change has been how Wilson gets the scores. Today, he has a laptop instead of the ticker-tape machine that spat out hundreds of yards of paper, showing every score in every sport that day.
"The way we got rid of that was they didn't make paper for the machine no more, so they had to give us a laptop," Wilson said. "It's a lot easier. A lot quicker, too."
Quick is Fuhs' specialty.
Since 1989, Fuhs has been posting balls and strikes on the center-field scoreboard. He's become a sort of Wrigley Field legend; he's mentioned on the stadium tours and is known by fans because he often has the result up before the umpire even finishes the call.
His secret is simply attention to detail.
"What I'll do is I'll watch the [umpire's] characteristics, the movements," Fuhs said. "So if he moves his foot to the right, I know he's calling a strike, so I can post it up a little quicker. If he calls a ball, it's a little more of a delay. He'll just stand there.
"I know all the umpires and their movements, and that's how I always get balls and strikes up there quick."
Fuhs' speed is definitely a skill, Wilson said.
"That's his one-of-a-kind thing. Nobody's like him," said Wilson, who has filled in for Fuhs on the rare game he has missed. "I'm a lot slower. Sometimes I make a lot of mistakes. That's why I don't like doing that. Sometimes you get in trouble if you put a ball up instead of a strike. I try to stay away from that."
The score panel sits in the press box above home plate, connected to the scoreboard by wiring along left field. The panel and wiring is original, the same box built and installed by Curt Hubertz -- who, along with his father, also built the Ebbets Field scoreboard.
From different vantage points, Wilson and Fuhs have seen the most memorable moments of Wrigley Field's last 20-plus years, from Sammy Sosa's home runs to Kerry Wood's 20 strikeouts. Being on the grounds crew makes for some long days, and day games after night games are always difficult. But the views and memories that come with working the classic scoreboard are second to none.
"I do take pride," Fuhs said. "I've been doing it for a long time. I enjoy doing it."