What would be involved in updating Hersey II’s to Hersey IV’s?

Having 30 years or 50 years experience of a brand has zero to do with now really, and the only Klipsch stuff I've ever paid much attention to are the "now" versions. Changes include vastly different driver materials, horn throat and phase plug technology, crossover components, internal wire...everything except how they look. I don't need to be "given" the efficiency part as that's only part of the tonal experience, and it seems that prejudice against a brand can last...remember the foam covered "L100" JBLs from the 70s? I do...relative to today they were not so great (a response curve like a big smile)...the new ones look exactly the same and actually are fine sounding (I heard 'em). 

Increasing the size of a previously sealed cabinet is clearly based on the design and tuning of the port relative to the woofer...I’m sure they wouldn’t bother otherwise. Also, Heresy IIIs (and other "heritage" models) simply sound excellent "leaving the factory floor" without ANY mods, and modifying an older model to bring it up to newer model standards isn’t the same thing...obviously...you clearly don’t need to "go big" for horns to sound great, as proved by the Heresy III...you simply need to listen big and stop worrying about porcine makeup. Klipsch manages to make horns that sound like music and provide astonishing levels of efficiency that the "woofers and a tweeter in a box" just can’t do (the efficiency part anyway), and having been able to compare Heresy IIIs to a couple of pairs of excellent albeit more conventional non horn "tower" speakers, over months with my own stuff, the similarities were more profound than the differences...other than efficiency, the fact that all great speakers convey what you give them is undeniable, and well thought out modern horn designs can simply do that more efficiently. My other non horn speakers were sold.

UPDATE...I found a pic and some info on a Klipsch community forum along with this quote from a Klipsch dude at RMAF: "In speaking with the Klipsch rep, he stated the change in the Heresy IV from the III is:  (a) the speaker is now a bass reflex speaker with port in the back, (b) all three drivers are updated based on what they learned from the Forte III, (c) the box is about 1" taller to accommodate the updated design, (d)  the riser is updated (in black and no curve), (e) grills will be updated , (f) binding posts are updated to a higher quality, and (g) in addition to the standard three finishes, the IV will be available in distressed oak with the linen grills." Supposedly to be announced 12/19.

Heresy IIIs are great speakers even in their stock form...I "damped" the mid horns on mine and it didn’t make much difference, but I think they’re simply an astoundingly great sounding speaker if used with equally good ancillary gear...in my case that means a great single ended tube amp among other stuff. The lack of deep bass is the trade off for a seemingly very even and accurate reproduction of the bass they do produce, and I prefer the adjustability of powered subs taking up the lower end as I like having an analog control of the deep bass (I eschew digital room correction if only to have the opportunity to use the word "eschew."). I’ve looked around for any info on the alleged Heresy IVs and wonder, Mrdecibel...where did you see that info?...curious. I sometimes think it would be cool to make a matching box for the Heresy mid and tweeter to look sort of like a mini LaScala, and mess with the woofer box for possible frequency extension...but don’t care all that much as my current setup works so well for me.