Thanks for the pix. I guess Lynx resistors and Erse capacitors are now the latest to use? The Erse caps are certainly a bit less $$ than the Sonicaps typically cost.
I performed the Ninja/Encore upgrade to my MTMs a few weeks back. On one of the cabinets, the cross-bracing was too close together for me to get the new crossover board into place, so I had to mount it on one of the cross-braces - as opposed to the side wall. It looks like splitting it as you've done on the X-SLS cabinet gets around any "tight" space issues.
Very nice. Thanks for sharing.