You should confirm it is spark related before going to far. Pull the plug wire that goes from the coil to the dist cap (dist cap side). Place the plug wire end against some grounded metal (engine) then try to turn the car over.
If you get a strong spark then the problem is elsewhere. This means fuel or internal machanical.
If you get no spark or the spark is weak then you confirmed you are on the right path in looking at the electrical system.
Simple test to prevent trying to solve unrelated problems.
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