Just having a little fun.
I expect the smallish carb, cam and heads will provide awesome low and mid-range power. That's a decent match with the build, actually. Those stock length rods leave you with rod ratio about like a stock 454 Chevy, which is not a hi-revver. If you have an auto trans, especially, I think you'll like it.
Power should peak around, what, 5600 RPM? I'd say 430HP and 475ft-lb torque. I'm not sure the carb will feed it enough at the high RPM, but I didn't run a calculation. Make sure you have adequate fuel line/pumps to feed the beast. And have fun.
Someone did a build with a 351 using stock Explorer heads and a XE276HR cam and made 350/400 at the crank. So, I think your estimate of 380/400 is low, even though you have a bit less cam. Still, I may be too high at 430/475. If you did make that much, I would have done a lot of things right.