I'm installing a pair of bar end shifters for my TT bike and I noticed that the rear derailleur shifter, the one with the clicks, seems to be on the left aero bar instead of right, I can't see it fitting right if I swap them over, is this normal for TT bikes to have the rear derailleur shifter on the left side instead of right? I have Shimano 9spd Dura-Ace shifters.

my campy shifter uses the left for the RD....they're normal brifters though....

If you're accustomed to shifting your rear derailleur with your right hand like most, you should mount that bar end shifter on the right aero bar. Bar end shifters can be mounted either way.