Hi Claude, will definitely keep you updated.
Currently, my Heresy's crossovers are modded based on this thread: https://community.klipsch.com/index.php?/topic/21969-heresy-crossover-mod-less-bright/
After reading your thread, I started searching this forum and found from this thread that JBL woofers can be used as drop-in replacement for the K22: https://community.klipsch.com/index.php?/topic/6768-damping-heresy-cabinets/
So a few days ago, I tried putting JBL 123A from my 4310 into my Heresies (see attached pics). After a few days of listening, I really like the sound. Faster, punchier bass that goes a little bit lower than K22. I'll try porting and stuffing the box first with these 123A to see how it sounds.
Also after reading your thread, I started to understand some speaker parameters, and found that JBL 123A has lower Fs (25Hz) than the Eminence (50 Hz). Does it mean anything? I'll try to tune the box to 40 Hz.
After playing with the JBL 123A, I'll try the Eminence (already arrived home).
Cheers :-D