I solved my problem and learned a lot. On the chance it will help someone in the future, I'll relate. Lord knows others' doing the same has helped me immeasurably.
Right turn signal was blowing fuse 9. 4-ways blew 11. This even after I replaced both rear light assemblies. The blk/grn wire to the RR turn signal showed ground. User "Spoke's" diagram helped me realize that the directional lights in the tach are in the same circuit and that's where I found some bad wiring, probably my fault, and a bad ground. Works fine now.
Things I learned: Per Spoke, I confirmed the short was not in the assembly. But I learned that the +12V has a path to ground through the bulb nevertheless and that a simple continuity detector was not good enough. There is 0.8 Ohms resistance to ground through the bulb, but not the 0.0 that would be a true short. So that's when I focused on the tach and found my problem.
Also, I used a newly purchased PowerProbe III. I could do what it did with a DVOM and a 12V source, but the PowerProbe was much easier and faster. But where it said "ground" I confirmed with the DVOM and measure the resistance.
Not often that I figure out a problem, fix it, know how I fixed it and that it is truly fixed. Let me bask in my glory for a day. Something else will come up.
see:
http://www.914world.com/bbs2/index.php?showtopic=341464