Gunner, Alik, Overlandr and Droptarotter: Thanks for the advice so far.
I realize that it might be "bad form" - cluttering up this mega-thread. The issues with my bike continue. In addition, the blue 1998 has started showing some post-rebuild hiccups as well. Thus, I'll be moving this discussion to my own "Three times the fun"-thread.
It has been a very long day for me, trying to diagnose all these problems. The fact that they are perhaps electrical (or at least related) and at times, intermittent, makes it quite difficult.
I think I may have some cold liquid headache medicine in my fridge, though...