Then he learned that the convention starting Monday would move from the 20,000-seat Pepsi Center to 76,000-seat Invesco Field for Barack Obama's acceptance speech on the final night, Thursday.
"After taking oxygen for about an hour ..." he said, letting the punch line hang in the air before continuing. "I said to my partner, one thing we're lucky about is that we've done so many stadium shows."
This time around, it's both timing and size that count.
There's the issue of shifting the convention from one venue to another in one evening, and having to work around football games scheduled at Invesco within a couple days of the convention's opening and closing.
The plan was to bring equipment into the stadium this weekend and then "caravan over" from the Pepsi Center after events wrap there Wednesday night, Kirshner said. "We'll rehearse a little and then show up Thursday and hope to do it."
Afterward, he has 48 hours to clear out for next Sunday's game between the University of Colorado and Colorado State.
Kirshner considers it worth the stress.
"I have my team with me, I know what we're getting into. It's not easy, but at the end of the day it's going to be one of the most historic things ever, and how can you not want to be a part of it?" Kirshner said Friday from Denver.
The event at the Pepsi Center isn't small scale, by any measure.
About 400 people, including stagehands and technical crews, are at work as RK Productions oversees the design, installation and operation of set, light and audio systems. The company also is responsible for entertainment; even signs and banners are part of Kirshner's portfolio.
But it's the video displays that tend to make the biggest splash.
"Every time you do one of these, you try to do something technologically advanced that people haven't seen before," Kirshner said.
That was a wall of 56 video cubes at the 1992 Democratic convention. This time around, Kirshner said, the set offers some 8,000 square feet of video panels with the flexibility to provide a changing background for each speaker.
At heart, a political convention is "a big corporate meeting," he said, which his company also routinely produces.
And no matter how dramatic the gathering or Obama's stadium speech turns out to be from a political standpoint, as a production it won't have the punch of, say, a Beijing Olympics ceremony.
"Their budget was a lot more than ours and they had a lot more free labor," Kirshner said.