Man oh man, oh man.
Sears Roebuck tune up shop would love you!
Now it's time for you to get some basic automotive training on the points ignition system.
Rotors, unless you got a Bosch, should last at least(hear that minimum) 12000 miles. Every so often you can remove the rotor, make sure the metal tab is not loose or burnt, take a piece of emery cloth or fine file and lightly file off the edge of the rotor, then REINSTALL it. Now the distributor cap. Biggest problem with the distributor cap is that it is not reinstalled squarely on the distributor body. So when you remove the cap, check the inside plug wire connection terminals, A little electronic cleaner every 5 THOUSAND miles(not 5 hundred) and a wire brush to clean the terminals would NOT hurt, but may not be necessary. The proper wire brush looks like a flattened bottle brush with the bristles poking horizontally like a flying saucer, so that you can turn them against the terminals, check for cracks. Make sure the center terminal is not broken and has the spring behind it pushing the carbon down onto the rotor. Easy way to check is to take your finger and push against the carbon, you should feel it slide freely in the cap. When you look at a new cap you will see how the carbon is slightly rounded. When it is flattened, then time to replace it.(course once upon a time you could get a carbon to replace it, not any more, sadly)..
Caps, should last a minimum, I say again a MINIMUM of 12000 miles, I know some cars that go 60K(like my Allison, MSD equipped car) no problem.
The condensor when it goes, usually goes bad right away, when first installed, or after it has been sitting idle with voltage applied to it for a continuous period of time, ie. key on, engine off, checking power to something...
Easy way to tell if a condensor is going bad is to look at the points, if you see a depression forming on one point and a hill forming on another then the condensor needs attention.
Coil, a non-Lucas coil should last minimum 100 thousand miles,(uh, if you didn't understand that, let me rephrase it ONE HUNDRED THOUSAND MILES.. Let me know when Amos gets close to that coil usage and I'll remind you that Maybe, just maybe it's time to think about replacing the coil.
Spark plugs. Minimum 12000 miles. Maybe pull them at 6000, to check for fuel deposit, carbon buildup, clean them and regap them, reinstall and run again. NGK BP6ES, are lasting approximately 30 thousand miles on most cars they come installed in.
Check your fuel filter. If it is clean, there is NO need to pull your carburetors off and rebuild them. Carbs should last minimum 30K miles before anything other than fine tuning, once they are properly set up new.
If you really feel like you've got to pay attention to them. Keep the linkage clean, lubricated. Pop the tops off periodically and spray the diaphragms with silicone lubricant, Make sure the diaphragm notches are in the proper inserts, refill the oil. Maybe every 6000 miles. If you feel like you've REALLY got to do something to keep your hand in Amos systems.
If you follow your recommendations on replacing components frequently, you are just wasting money that could better be spent on Food, Gas, Your Wife and Yourself!