Yes, I finishsed it last September. So far zero issues with power shedding but the real test will come this summer. I have a single Magnum 2000W PSW inverter and it does just fine.
Here is a link to a forum doc that I uploaded, detailing my install.
I like your idea re: the transfer relay. I'll save that idea if I run into problems. All in all one of the best mods I've done to date.