original owner told me swingarm was upside down. upon inspection, this is not possible. it seems the linkage that holds the rear shock is on the bootom instead of the top. is this a good idea? should i put it back, and can i?

 

The linkage is supposed to be on the bottom. What has happened is that it is flipped 180 degrees along the N/S axis of of the bike which lowers the point where the shock mounts to the linkage therefore dropping the rear end about 2 inches.

While this setup does change suspension ratios/rates and is not recommended for jumping it does work well on the bike for many recreational riders, a few members of my riding group included.