371 build W/Big Mouth heads

MOPAROFFICIAL said
I wonder the difference in power between a 1 5/8 to 1 3/4 step header w/2 1/2" pipes vs 1 5/8 header to 3" pipes same mufflers.

I am seriously contemplating shortening these up about 4 inches and trying a merge collector with a 2.25" choke. J.Rob