Nitrous plumbing A1A...??..

Keep it simple to start with.
Two plates and two sets of jets, one for each carb. One fuel solenoid and one nitrous solenoid. Yes, you can tee the output of one solenoid out to two carb plates, just like one solenoid can feed several fogger nozzles.
Your twin plate setup will double your expected jetting level output. That is to say if you want to add 100 horsepower, you need each plate jetted for 50 horsepower, so the total amount flowing adds up to your expected number. The nitrous and fuel solenoids are rated for what they add on a single plate. If you were to try 250 horsepower jetting on both carbs, theoretically speaking, your single kit solenoids won't supply enough, and that is when more solenoids are needed.
After that, make all timing and fuel supply adjustments based on total power added.
I have run 250 horsepower jets in a single plate Cheater system for a lot of passes on mild 383. It's pretty safe if you don't get greedy with timing.