Further update:

Long story short, the stem was the diameter (both for the steering tube and the handlebar), but was a bit too long. The bike is a small frame (20") and the stem would have been too high. Argh!

After some research on the forums, I decided to try and cut it down (a little less than an inch). The andgle was a bit tricky, but I managed to cut it properly with just a hacksaw and a vise. Cleaned it up with a file, and it appears good to go.

This whole wrenching thing may start to become addictive.