Help with stock EFI

I disagree with you on the RE. I would stay hydraulic. Way easier and cheaper to deal with "with trouble" and if you decide to go with manual valve
Not if you’re using an obd2 ecu. If I was doing it and I had to have a 46rh then I would use an obd1 ecu and harness. It will be easier than changing sensors and modifying an obd2 set up to run with the 46rh.