2bbl to 4bbl GS help

Hi everybody, I need some help with converting my 2bbl skylark to a 4bbl with a VS air cleaner. So here's the DL... all I'm trying to do is open the engine up a little bit. It's a 1 owner car, only repaired with stock parts. I have a cast 4bbl intake stamped for 1972-73 year. Q. What intake manifold gaskets do I need to use, do I need to plug any ports? I have restored a 350 GS air cleaner assembly that I really want to use with my GS hood. Q. Can I use an aftermarket carb on my cast intake WITH my GS air cleaner and still clear the hood? I want to run no more than 600cfm. I will not be camming or putting new heads. The only other aftermarket part I will be running is a set of Doug's headers. Q. Exhaust recommendations? Also, what gasket set do I need to run these headers? Part #? Thanks for all the help. Any other recommendations are appreciated. So far it has new spark plugs, wires, distributor, I have stripped stock valve covers and a 4bbl intake in caustic & painted them high temp red. I cleaned up, soldered/heat shrink the engine wiring and rewrapped the wiring harness nice & tight. I put a new voltage regulator and alternator in a few months ago and it was running good.

I would use the intake gasket set for the year of the heads. The only difference is the shape of the exhaust crossover passages between the heads and intake. What I see is a 1970 Buick 350 engine. This gasket set should work fine,

https://www.rockauto.com/en/catalog/...ket+/+set,5424

You shouldn't need to plug anything. The 72-73 intake should not have EGR or AIR injection.

I think it is very foolish to run any carburetor other than the stock Quadrajet carburetor. That will give you the best performance and gas mileage hands down. Having said that, it is very important to get the Quadrajet built for your engine. The Quadrajets were built specifically for the engine size, make, and year they were meant for. You therefore cannot just bolt on any Quadrajet and expect it to run right. The Quadrajet for your engine was 750 CFM. The Quadrajet is an on Demand secondary carburetor. It will only flow what the engine demands. While you can bolt on one of the cookie cutter carbs like the Carter AFB clones or a Holley, they will not perform as well as a good Q-jet. In addition, you cannot bolt either of the aforementioned carburetors onto a stock intake without an adapter. Both the Carter clones and Holley carburetors are squarebore carburetors, different bolt pattern. The adapter will give you possible hood clearance problems. I recommend you get a Q-jet built by someone who knows what they are doing. I highly recommend Ken at Everyday Performance.

http://www.everyday-performance.com/...oduct=11494619

For exhaust, I would run a nice 2 1/2" dual exhaust. Muffler selection is a very subjective thing, but I recommend the Walker 17749 long case mufflers. They are hard to beat IMO.

https://www.summitracing.com/parts/w...SABEgLOAfD_BwE

TA Performance sells a nice exhaust system, or you can look in the Summit or Jegs catalogs for a header back exhaust system.

http://www.taperformance.com/proddet...rod=TA%5F2007A