Kansas City, Mo. ? Plans to create a rail museum at Union Station by early next year that would be among the top such attractions in the United States have been pared down because of money.

Six months ago, Union Station’s board voted to pay a Milwaukee collector $650,000 for 11 antique rail cars and a vast collection of railroad memorabilia packed inside them. A consultant estimated the museum would attract 250,000 visitors and have first-year admission revenue of $1.3 million — with an operating surplus.

Now the station is looking to fix up five of the rail cars for tours at the museum and sell the other six, along with some of the duplicate memorabilia. The projected opening date is pushed back to the end of 2005, and attendance estimates have been lowered to between 100,000 and 150,000 a year.

Sean O’Byrne, shortly after being named interim director in June, persuaded the Union Station board to buy the rail collection. He said he still thought the rail museum could succeed, but he was downplaying expectations so there would be some wiggle room when it comes time to determine that success.

“I’m going to take what the consultants say, skinny it down, and do something we can afford,” O’Byrne said. “The thing we want is ultimate flexibility with the collection. We want to be able to grow it or contract it, depending on the market, and that’s why we are starting with conservative numbers.”

The collection was purchased with money left over from the 1996 bistate tax that funded the station’s renovation. O’Byrne said another $1 million was needed to get the collection ready and set up the display.

Union Station has struggled since it reopened in 1999. Attendance at its feature attraction, Science City, fell short of a consultant’s expectations — but still is estimated at 400,000 annually.

About 30 volunteers, directed by consultant Pete Hansen, spent two months sifting through rail memorabilia that was in the rail cars and cataloging it in a database.

There are more than 5,000 pieces of china, 1,000 glassware items, 2,500 pieces of dining room paper goods, thousands of ticket stubs, maps, travel brochures and pins.

Thousands of duplicating items will be sold, but neither O’Byrne nor Hansen could estimate how much money that might bring in.

The memorabilia will be displayed in a large room now used for temporary exhibits at Science City, and a storage area will be converted to hold Science City’s temporary exhibits.

Hansen said the museum would give visitors the full rail experience of people who traveled during the passenger lines’ heyday in the 1940s and 1950s. Visitors will go to a station of that era, board trains from that era and see how life was on those trains.

“Our museum will emphasize the human stories and not so much the hardware,” Hansen said. “That will make us fairly unusual in the rail museum world.”

There are more than 225 rail museums in North America. Well-known museums that are much larger than what is envisioned at Union Station attract far fewer visitors each year than what the Kansas City museum would be expected to draw.

O’Byrne hopes Union Station’s location and history will pull visitors in from a two-hour driving radius. He expects the train museum to draw people on its own, plus bring in some who came for Science City and other station attractions.

Molly Butterworth, collections curator at the Museum of Transportation in suburban St. Louis, said the challenge for full-fledged railroad museums is to get the attention of the younger crowd.

“Unfortunately, we are losing the generation that rode trains every day and understand them,” Butterworth said. “We have to re-create the experience, and it’s hard to do that in purely hardware terms.”