What about structure?

what is your reasoning behind having two?

You would be better off with one. With two, that just opens up liability problems, and messes up the timing of each GC's subs. Also, the GC takes their cut as they have to make a living and they orchestrate the whole thing, you would have extra cost with a second GC.

If there are specific pros that you would want hired, let the GC know.

Unless I knew the other GC, I'd be very wary of such an arrangement.

That structure opens leaves the door open for lots and lots of finger pointing. No matter what the issue, it will be at least partially the other GC's fault.

A friend of mine is currently involved in a large commercial project with two GC's; one for the main floor public spaces and mechanicals, the other for the more individual spaces. Each week is a new story, like the one guy decides to shut off the water to the entire building instead of going section by section and the other guy has dozens of people on site expecting to have water and toilets available.

I think you'll be best served by selecting a single general contractor with the capability to manage the entire project. If the total scope of your project is scary for the GC's you are considering then keep looking until you find one comfortable with the full scope.

If you are willing to act as the general contractor you could hire a contractor for each trade. There would be no advantage to splitting work arbitrarily.