Yeah, if you're going carb, you'll need a regulator. You might be able to put it near the tank so you don't have to run that much extra line.
On the returnless system, the regulator is actually in the pump module. So no separate regulator is needed.
With the Camaro pump being at 58 psi, that might be close enough that it would work with the Magnum injection. If not, there is a regulator/filter combo that came on Corvettes that might take care of the issue. Not sure, but they were discussing it in the new Hemi swap forum.