I wouldn't bother to try and modify the stock inner plate. There is just no the plate can be modified with out butchering it. I ended up using the Stellings inner plate, but I wasn't able to clamp it as tight as I needed to keep the box from slipping. Maybe the IMCO plate will allow you to really crank on the bolts.
Things have been better. Sold the house last summer but got beat out (repeatedly) on it's replacement. Faced with a housing gap we were forced to accept an offer and we moved back in with my mother-inlaw. We finally bought a house and were moving forward with it's closing when I got laid off. The market is so crappy that I'll be off for at least 6 months. You know that you've hit bottom when living with your mother-inlaw isn't so bad.