Powerhour

hey everyone, I have a 88 D250 and I'm looking for some good low end power as I use it mainly for my camper.
im looking for some options on a intake manifold, carb and a cam.
I am thinking a Holley 600-650cfm (don't know which model) and maybe a edlebrock performer? I'm just looking for some options. I'm not looking for crazy peer just something that would haul my camper nice and to have some fun with out it on! Only thing done to it is true dual exhaust.
any input is greatly appreciated

Coronet 500

Doing the same thing with same thing carb and performer on 323 ci. Comp Cam XE 256 H, 3.55 rear axle ratio. Cam has tons of low end grunt and suprising top end up to 5000 to 5500 rpm. For the 360 maybe just one size bigger.