Hitachi SU tech pages
Try this site too. It's listed in the "Web Links" under Tech info.
I think you have made your decision, but I'll throw in my 2 cents anyways. I'd lean toward the SU's mainly because I don't like the 32/36 + adaptor plate+ stock manifold combo. I used to have this in my car. It worked ok.
Now I have twin 38mm Hitachi SU's. I seem to get a little more power from these. I'm also still trying to understand how, when and why they work. But they do work and I know they're not in tune. I haven't check to see if they are in sync for over a year and the damper on one doesn't feel as stiff as the other. Did i mention the homemade linkage with no way to adjust each carb without disconnecting them? How about the 34mpg?
So don't worry about these things not being perfectly in tune. You can mess up the adustments on a 32/36 just a bad as you can an SU(type) carb.
I think 2 38mm openings feeding air/fuel is better than a 32mm and a 36mm opening that gets necked down by the adaptor plate on a tiny stock intake.