CHEYENNE, Wyo. - In a makeover of extraordinary proportions, scientists have dismantled a 75-foot-long sauropod dinosaur that roamed Wyoming 150 million years ago and will rebuild it to reflect the latest paleontological research findings.

The fossil display of the plant-eating Apatosaurus that had dominated the University of Wyoming Geological Museum in Laramie for about 45 years will be worked on for a year and then returned to the museum in 2008, according to Brent Breithaupt, director of the UW museum.

"It's basically like extreme home makeover, only this is extreme dinosaur makeover," Breithaupt said Wednesday. "Everything from the tip of its nose to the tip of its tail."

The Apatosaurus fossil is one of only six on display in the world, he said.

The UW fossil display is about 60 per cent actual bone, which were unearthed in the early 1900s 70 miles north of Laramie, with the rest of the display cast from molds. The display was assembled in 1960 by UW professor Samuel H. Knight, who died in 1975.

"We will be able to add some of the dinosaur's bones that professor Knight didn't have at the time to improve the display's looks, such as posing it with its tail in the air instead of dragging on the ground," Breithaupt said.

Most of the fossil was dismantled this month by experts from Treibold Paleontology Inc., a firm from Woodland Park, Colo., with expertise in casting skeletons and fossil mounting.

However, the skeleton's large hip bones, which weigh about a ton, were not dismantled because they are too heavy to lower from their 15-foot perches, Breithaupt said. Those bones will be left in place and worked on in the museum.

"Lowering a ton of bone would be very, very difficult," he said.

Treibold will make a cast of the fossil that will be available for other museums to use for displays, Breithaupt said.

In addition, Treibold will make the pieces cast from molds more bonelike in appearance and lighter and easier to manipulate for display.

While the skeleton is dismantled, the fossils will be available to researchers worldwide, Breithaupt said.

While the Apatosaurus is gone, new displays featuring duckbill dinosaurs and a sea reptile on loan from Treibold will be displayed.