The intersection of Halsted Street, Fullerton Street and Lincoln Avenue later Thursday afternoon. View Full Caption DNAinfo/Mina Bloom

LINCOLN PARK — City officials aren't the only ones fed up with the Chicago Republican Party's giant sign.

The sign, which was installed by the group at 2420 N. Lincoln Ave. last fall without a permit, is covering a big window in Tom Alcock's psychology office — and he's not happy about it.

"This has been really hard on me," Alcock said. "I've lost sleep and pounds trying to protect my business."

He said his opposition has nothing to do with the sign's content.

"It could be any sign. It could say, 'Feed The Starving Children.' Can we just move it? This isn't as much a political fight, as it is one about how [they're] taking away my space. I respect your space. Why wouldn't you respect mine?"

Alcock moved his psychology office into the building in July.

The Chicago Republican Party moved in a few months later and installed the sign, which reads, "Chicago Republican Party, Chairman, Chris Cleveland."

Cleveland acknowledged he installed the sign without a permit because he believes the city process takes too long. He wanted the sign up during the primary election to attract volunteers.

The city is now threatening to charge the property owner — not Cleveland — $1,000 each day the violation exists. But Cleveland has no intention of taking the sign down and expects to sue the city.

Alcock said not only does the sign violate city law, but it also violates Alcock's lease.

Yet Cleveland believes the issue is a matter of principle.

"I refuse to ask permission from any government entity before engaging in political speech. It's unconstitutional and offensive," Cleveland previously said.

Alcock said the sign not only darkens his office, but it also confuses his patients because many of them come in thinking his office is affiliated with the Chicago Republication Party. It makes matters worse, Alcock said, that he disagrees with the group's political values.

"Our job is to help people. It sucks when I get into my office and I see this thing that reminds me what I built is being diminished or being looked at in this way," Alcock said. "Sometimes I hate going into my office and that kills me. I've done a lot to build my business."

Despite this, Alcock has decided against suing the Chicago Republican Party in hopes the group will move out when its lease is up in about six months.

He's also decided against moving because he has invested a lot of money into renovating the office. Plus, he said working at the corner was always a dream of his after being raised at Diversey and Sheffield avenues.

In response, Cleveland said he's sorry Alcock is unhappy, "but that's between him and the landlord."

"This is about the the city of Chicago coming after Republicans because they're Republicans. Had I known this was an issue, I would have made sure the landlord had it straightened out beforehand," Cleveland said, referring to Alcock's complaints.

Cleveland said he's tried to be accommodating by adjusting the sign to let some light in. But that's not enough for Alcock.

"I've told them from day one, it's an illegal sign," Alcock said.

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