I finally got the bottom headset cup into my frame! BUT, there is a space, barely enough to get my fingernail into, between the top of the bottom cup, and the bottom face of the Tamer headset reducer. Is this space bad? I have tried several times to get the cup in farther but to no avail. Thanks guys!

Is the gap equal all the way around the head tube? If it is touching anywhere it means your head tube needs facing. If it is not touching you might get away with it. There could be a slight ridge inside which is keeping it from seating all the way. However, it may seat while you are riding and you'll have to readjust the bearings. Check after each ride.

What are you using to install the headset? Somehow I think your answer may frighten me. ; ) What kind of headset is it also?

Ha ha!! I made a headset press. I have a Bicycling magazine that gives instructions on how to build one. It works pretty good. I think I had a hard time with the bottom cup because I was so scared of screwing something up. My headset is a FSA Orbit DL.

Fubar.

You have to chamfer the bikes head tube for some headsets to fit properly, this takes a special tool, and there should not be any space there.

This especially applys to Cannondale and other alu. frames, better go get it checked out.