Something this old will have some built in problems. First is as gas evaporates it leaves behind a varnish. This varnish build up can reduce the size of the machined interior dimensions inside the metering circuit of the carb. This will result in the wrong mixture of air and fuel to your engine; which is probably what you think of as a bad tune-up. To fix this the carb has to be disassembled and "boiled" in an organic solvent that will dissolve the varnish but not destroy the chemically reactive metal the carb is made out of (an alloy of zinc, tin, lead, and aluminum). Then the cleaned and dry parts are reassembled with new gaskets and small parts that wear out that come in a rebuild kit.
The other problem you will discover is that chemically reactive metal carburetor has chemically reacted with the acidic alcohol and the water it absorbs to corrode the interior of and thoroughly destroy the carburetor all together. Alcohol was introduced into fuel long after the last carburetor was installed on a car back in 1986. The fuel tank (zinc plated mild steel) will corrode as well as the rubber fuel lines made of neoprene rubber dissolving under the attack of alcohol. The paper fuel filter will also dissolve due to the water absorbed by the alcohol. Nothing on your car was ever designed to work with alcohol in the gas tank.
Modern fuel systems are made of stainless steel (tank and fuel lines) with fiberglass or spun stainless steel fibers thinner than a human hair (10 micron filtration) inside the fuel filters to deal with alcohol. Rubber neoprene fuel lines are all lined with Teflon plastic and have a green stripe on the rubber hose. Current carburetor parts built to withstand alcohol are colored green instead of blue or the usual grey color. Holley and new Carter AVS carbs sold under Edelbrock's name are anodized (a different color such as red, black or purple from the usual dichromate golden bronze plating, but it could be any color they want. Or they are painted inside and out with a clear epoxy paint after they buffed the solid aluminum body to a high shine.
There isn't to my knowledge a replacement Rochester 2GC carburetor body that is alcohol proof, but they do sell rebuild kits with green gaskets that are immune to alcohol. You can use a 100 micron sintered bronze strainer in the carb inlet to replace the paper filter. An you can install a 10 micron fiberglass fuel filter in the fuel line to filter all of the fuel if you have an electric fuel pump to push the fuel through the filter at the gas tank and before the carb if you want.