The 377 is typically a high RPM engine but without knowing the cam, and valvetrain specs its hard to say what the RPM range should be. unless your willing to disassemble the engine and check it out, along with looking at the connecting rods and pistions I personally would never try and rev it to 7500-8000 rpms.
First thing I would do would be add a quality set of long tube headers, and a good high flow exhaust system. Stock manifolds will kill upper rpm performance. On an engine like this I think the Q-Jet would be my choice, just make sure you have it tuned to your engine. That's the real trick