The 18 rough riders of the Sacramento Sheriff's Posse are headed to Washington for their latest assignment -- not to track down desperate characters in the nation's capital, but to help lead the 50th Presidential Inaugural Parade.

Naturally, they're bringing along their matched Palomino horses, silver-encrusted saddles and sequined western outfits (including the white satin shirts with a giant golden bear hulking across the back).

Unlike their Wild West counterparts, however, they're leaving the firearms at home. "Not allowed," said Undersheriff Dee Reynolds.

From Sacramento, Calif., to Sarasota, Fla., from the mountains of Montana to the schoolrooms of 17th Street, participants in Monday's parade are getting ready, with varying degrees of flamboyance and nerves.

In all, about 12,000 military personnel and civilians, more than 700 horses and 21 dogs will take part in the procession that moves from the Capitol to the presidential reviewing stand at the White House.

Each state has an official representative (California and Texas, the home states of the president and the vice president, have two) and each state has a grand marshal. While the majority of states are sending their governors to fill the marshal's role, others are sending stand-ins.

Count among them the known and the not-so-well-known: Sally Ride, the first American woman in space; Steven Meredith, president of the Future Farmers of America; Alfreeda Marshall, Arkansas Teacher of the Year.

Some were invited because of titles they hold or public services they perform; others because of acts of heroism.

Ovetta Wilson, a 56-year-old Navajo who speaks no English, rescued six children from a school bus that was trapped by a flash flood near her home in New Mexico last October.

William Holsclaw, a 13-year-old boy scout from Nevada, was burned over 40 percent of his body when he rescued his two brothers from a burning trailer in February.

And, acting alone on Dec. 13, Sheriff Johnny France of Madison County, Mont., captured two men accused of kidnaping and wounding U.S. biathlon team member Kari Swenson and killing another man who had come to her rescue.

"Going to Washington for the inauguration probably scares me more than sneaking up on those men," said France, 44. "That was part of my job."

Other participants are looking forward to the inauguration with confidence.

Leslie Patten, 20, Miss Rodeo America, is coming to Washington with the ambition, admittedly unrealistic, to catch the ear of the President.

"I want to talk to him about the farmers," said South Dakota's grand marshal. "They're in sorry shape."

Patten would also give the president pointers on sprucing up his cowboy image.

"He may be putting on that image," she said, "but . . . well, I appreciate his attempts to be a cowboy."

Artist Harry Jackson from Cody, Wyo., is coming to town with the very satisfying knowledge that three of his bronze Western sculptures decorate the Oval Office. Jackson, 60, also did the 22-foot-high likeness of John Wayne on horseback placed on Los Angeles' Wilshire Boulevard last June.

"I find my invitation a particularly important honor," Jackson said yesterday, "because I'm an artist and inaugural committees don't usually recognize artists. It's always athlete of the year or teacher of the year or an astronaut or something like that."

The inaugural committee is picking up the tab for transporation and two nights of lodging for the 19 grand marshals who are not governors. All others have to pay their own way.

While grand marshals such as Patten and Jackson are traveling many miles to be in the parade, other participants will travel a matter of blocks.

"The tension is building around here. We don't want to mess up in front of the president," reported Jeffrey Bowman, 17, presi (National Caucus of Labor Committees photo) Capitol and 17th Street. The band is the District"s official representative in the parade; its counterpart in Maryland is the Glenelg High School marching band from Glenelg.

Tucker Eskew, inaugural committee spokesman, said the point of the diverse participants is to inject variety into the parade -- "all kinds of different things."

Which brings us to those 21 dogs.

A spokesman for the dogs, huskies to be precise, was unavailable yesterday since he and the animals are en route to Washington. But here's what Eskew supplied about the official representatives of Alaska:

Their drivers will wear traditional Eskimo garb. Their sleds will be modified with wheels, instead of runners, to accommodate Washington's lack of tundra. And they will be accompanied by an equally prestigious participant, Col. Norman Vaughn, a member of the first Byrd expedition to Antarctica in 1928.