Dual 32/36's?
I assume that you must have a carb set up similar to the L series one that MatBigHat posted a picture of recently.
Seeing as how I've never seen a nitrous plate for those carbs, I'd say your best bet is to use nozzles.
Just use two. Place them in the intake runers, right before where they split into to two to feed each cyliinder.thing about nozzles is, they hit hard.
If you go to the nitrous oxide systems website, you can download the jetting maps for nozzles on a small shot. they have a table from 6HP up to 60. (Per nozzle)