Hello!

I'm currently rebuilding a K100 engine, yesterday I did the daunting task of replacing the waterpump seals, shaft, impeller etc. 
I followed this guide (http://www.kforum-tech.com/mechanical/oil-pump/oil-pump-seals-replacement.htm), everything went pretty smooth until I was finished with pulling the shaft thru the ceramic seal. Following the guide enclosed I pulled the shaft until the gears was flush with the housing, I then noticed that the gears was rubbing on the inside of the waterpump. I guess somehow I must have pulled the gears to far? I tried mount the impeller with the bushing, somehow this seemed to help a littlebit, bit I can still feel a tiny bit of resistance when rotating the gear. 
Have anybody had a similiar experience, could this be because of some production problem on the new gear shaft, out of tolerance maybe? 
After blowing out the first aluminum dust/chips made by the rubbing, it seems to be clean now, even after rotating the shaft a bit. I'm still unsure if i should get a new seal and start the process again, any thoughts? 

If a new seal is fitted correctly, then there will be some appreciable drag on the shaft from the seals - it certainly won't spin freely. 
The picture seems to show scoring from the idler/smaller gear, not the main impeller shaft. If you've managed to clean this up, and removed any burrs from the gear so that is turns without any further rubbing or galling, then it should be okay.