I'm going to have the tranny bells gold or nickel plated. The new chassis is nickel plated. I'm considering pulling the caps and replacing them with the Triode Electronics quad-cap upgrade board. No improvement, but will cleans things up. Also going to replace the single tube PC board with the Troide Electronic dual tube upgrade board. Will go with a pair of Sovtek KT88 tubes. Also will replace all the connectors. Will use gold jacks compatible with the JBL's and the Phase Linear gear.
These are the subs I built to support the L100's. They are walnut and as close a match to the JBL cabinets as I could get. Real thumpers. Floors vibrate and you can feel it in your gut! They have JBL blue foam grilles that go around the aluminum supports. The top cabinet stacks upside down on the bottom cab - not as they are pictured.