Whew. Done. I had to come back and re-read the posts after I got the tank off. Holy plastic vacuum 'T', Batman! I was expecting 2 separate lines, not a 3 into 2 network of vacuum routing. I'm sure there is a reason, but it seemed overly complicated to my simple mind. At any rate, got the throttle body return line plugged, and routed the vent to the back wheel area. It felt like the idle speed was a little faster, but that may just be me or coincidence (colder than my normal riding temps). I'll get a proper plug for the throttle body, and double-check everything for vacuum leaks. Then, onto the exhaust and headlight.
Thanks everyone for your help. It helps my confidence to read that others know what is going on. I'm fairly mechanically inclined, but I definitely don't like to blaze the untraveled trails. So, thanks again, everyone.