You can't. David413 is currently updating the fleet to 3.8.2 level.
Two vessels are available. Discovery as part of the STS-114 Expansion Pack and Endeavour (as Endeavour3.8.2). Links are
available from the M6 Orbiter Addons Forum.
David removes older revisions of his vessels as a new revision becomes imminent. He prefers to maintain control of their
distribution (as is his right) so others who have older copies should NOT email them or make them available for posting.
If you think this sounds a little quirky, remember David produces amongst the best of the shuttle addons. His continued
development of them should be encouraged by following his wishes. By doing things his way, you can be assured that his addons
work with the latest releases of Orbiter, unlike the works of other others who throw something out there and forget about
them. We would be a lot better off if more authors followed David's example.