heads and intake manifold set up for 318. j heads available.

im almost gauranteed a set of J heads from a 360 in the junkyard. i know i need to have them machined to reduce the combustion chamber size. what kind of intake manifold should i get for it? single plane or dual plane? i know ill probably go with a mild cam, for driveability on the street, since it will be my daily driver. should i replace the valve springs and/or valves since the heads have been in the trunk of an imperial for some time now (still on the motor though).

how should i work this whole situation out? im kind of limited on cash, but, i can save it up for the RIGHT items the first time, not whats cheap now and what replaces broken parts later...