I found 50s wiring for the bridge was to trebly/spiky and didn't give me the sweep of the tone control I wanted. I ended up with 50s wiring for the neck and Modern wiring for the bridge - this gives the awesome p90 clarity in the neck that I was craving. Here is what I did after acquiring a stock, used 2019 Casino (which had the usual muddy neck pickup, bridge buzzing and tuning/nut issues): It took me quite a bit of research to figure out what would work so hopefully this can save someone the time.
I wanted to post my completed project to convert a MIC Casino to a Poor Man's ES-330 (or MIA Casino) in case anyone else wanted to upgrade their Casinos (and wondered what parts fit and/or are required).