Inspired by this Forte thread (thanks Jesse), I decided to give the A55-G drivers a go in my Chorus II setup. I consulted with Mr Crites and found a way to mount the driver directly to the stock horn in the Chorus (the trick was having enough depth in the cabinet and I ultimately had 1/2" to spare). After more than a month of listening to the A55-G installed in my Chorus II speakers, I've had some time to process the differences over the stock K61 mid driver and there's really no comparison. The overall midrange sound is much better - smoother with more detail and range. I'm very happy with the change over from the k61! Thanks to Jesse and Bob for the help!