I am going to throw this out there for a friendly debate.
I will be putting a mild 360 in my 87 D150 that will have long tube headers.I have all of the mufflers and pipe already to run either a 3" single exhaust or a dual 2.5 setup.Make an argument for one or the other if you like.
Motor is 9-1 .030 over 360 with a smallish(torque)cam,aluminum intake,4bbl in the 600-650 range likely,and some light porting on the heads.
Stock tranny/converter and will have no more than a 3.55 gear.

What would you run and why?