Article II does not speak of “eligible to election” rather it speaks of “eligible to office”.
Article II does not differentiate between pre- or post- election, at all times an ineligible person shall not be President.
If you dispute a point made here http://www.freerepublic.com/focus/news/3045713/posts?page=375#375 do so specifically.
Candidates run for office.
We’ve had close to one-hundred test cases between 2008 and today of attempts to remove from office an allegedly ineligible person who assumed the office of president.
The vast majority of those legal challenges were dismissed on grounds of standing (wrong Plaintiifs); failure to state a claim upon which relief can be granted/non-justiciability (not the job of the courts); or political question (no real legal issue involved).