Dave - very nice, man

I saved that guy in my ebay favorite sellers - he's worth checking into for boards - great looking stuff (cheeeeeeeep!)
jt1stcav - I did each 'mod' separately so I was able to gleen which ones were beneficial and which weren't for me.
Re-wiring > near zero betterment (maybe a bit, but I was straining to hear the change. Then again it was just 18ga OFC, nuthin' fancy)
Plast-i-Clay inside walls > very sizable; perhaps the most beneficial (the walls were very, very bad 1/2" particleboard, so no wonder

) An inert cabinet seems more important then average parts (as the drivers and crossovers were originally very average)
Lead shot at the bottom > reasonably good betterment...tho I'd expect only minor betterment after the large increase in focus and resolution after Plast-i-Clay'ing the walls
Acousta-stuf >
major betterment in improving the midrange. Too much and the bass was overdamped however...took some time to get the balance right.
New GR Research woofers > A little more extension, a little better resolution. I had clayed the cheap stamped baskets of the cheap Peerless' that they came with originally, and added tiny clay dots on the cone inner and outer and this helped critically damped things well beforehand. The cheap Peerless was fine with these upgrades...the GR Research swap-ins (no crossover change at all) benefited it a little - especially in bass extension.
Tekna-Sonic Vibration dampers > I put these one and thought they were a crock of shit for $100.00. I left 'em there for over a year figuring that they didn't make it any worse. One day I pulled them off...and began wondering what was wrong with my system. Put them back on and all is right again. They do seem to change vibration into heat as they claim. Small, but beneficial.
Maple blocks and points (done together) > Worthwhile, about on par with the woofer swap-out. For $125 total, I'm pleased with the effect - especially as these can be used with other audio adventures of the future.
Ciao, John