I would ditch the dual exhaust idea. It only adds weight and gives no performance improvement over a good 2.25-2.50" single exhaust. It sounds like you want a peppy driver with good mileage so one of the OD auto transmissions with some fun street gears would help a lot. Up the compression to somewhere around 8.5 static and 7.75 dynamic. That will let you run standard pump swill. Have the head and/or block shaved to reach your compression goals, then pocket port the head and install larger valves, 1.70/1.45 or so. Triple Webers are sexy as hell but complicated to tune and not likely to give a ton of real world improvement over a super six setup or a small 4-bbl intake unless you want to get real serious about the rest of the engine. Add a good free-flowing exhaust.
@moparmarkk has a set of long tube headers for sale that should fit your car and would be an excellent choice. Depending on your goals I'd talk to Ken at Oregon Cam Grinding and see what he suggests for a regrind that would fit nicely with the rest of your parts. And hell yes, if you have the coin for it, a Torqstorm would be the bees knees but if you go that way make up your mind before you do the rest of the engine - a blown motor needs different parts and specs than a NA motor.
