I've been offline for a while because of ApolloCon, but I'm back at it. My XYL, KD5SBI, has expressed a desire to do PSK31 on 2-meters FM (and I've confirmed that there is such a thing) and has indicated that she understands the need for an interface box. To that end, she suggested that I purchase the UMI SCI-6 and assemble it, for it is a kit, for her birthday, which is coming up soon.
I've bought it, and assembled it, and I've built cables to go between it and my IC-706MkIIG so that I can test its functionality. If it works, I'll probably buy and build one of my own. It was an easy hour or so assembly (assuming I did it correctly) and I've always wanted to run digital modes on HF, and the price (around $30 shipped) couldn't be beat.
Next, I have to build the cable to go to her radio and I'm done.