Well, I have been away from the shop for a while but have gotten down to it with this engine. The side clearances on the rods are between 15 thou and 18 thou. It seems that I might have been running the rod bearing clearances a bit tight, because when I pulled the caps on the rest of the rods, I found a problem. #s 3, 4, 5, & 6 looked fine and had a clearance of about .002 (perhaps just slightly under, but well over .0015). #s 7 & 8 were just starting to pull the bearing material, and had a clearance of .001.
I have cleaned up the crank (the first and last throws had trace scratches), and now have a clearance near .002 (using the plastigage shows just under .002, but well over .015).
Hoping that this solves the problem.
Thanks for the advice and tips.