There is absolutely no reason to go to a Holley, and you don't need an electric pump, the mechanical pump is all you need. You are literally asking for trouble by going electric. All you are doing is adding more failure points. Any carburetor re builder can make your carburetor like new. Make sure they use ethanol resistant parts, and check the throttle shaft for worn bores, it can be bushed. I recommend Everyday Performance. He rebuilds Quadrajets, but I bet he can service your 2bbl. Contact him and ask. Ken does great work.
From bone stock to street or sport, Everyday Performance can help you bring your cruiser or daily driven muscle to life
everyday-performance.com
In addition, your original Rochester carburetor has been calibrated for your engine. A new Holley will have a generic tune, it's meant to work on a bunch of engines, so it isn't optimized for your engine. It will very likely run OK, but it will probably deliver less fuel economy.
Your fuel pump may be tired or damaged from the ethanol in pump gasoline, get a new one, they are cheap.
Fuel & Air Parts and More for Your 1964 BUICK SKYLARK at Reliably Low Prices. Fast Online Catalog. DIY-Easy. Your Choice of Quality. Full Manufacturer Warranty.
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There are lots of options for an electronic ignition from points replacement units to new distributors.
These are really nice and budget friendly,
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