Franklin was no Quaker. Your ignorance of his religious/philosphical positions rather disqualifies you from being an authority on what or who is conservative or isn't. You seem inordinately disposed to labeling people one way or another.
Franklin's, and other of our "Fore Fathers'" (as you write it) positions on religion were not as evangelically orthodox as so many latter day "conservatives" would have it. For a glimpse at Franklin:
To Ezra Stiles, 9 March 1790 You desire to know something of my religion. It is the first time I have been questioned upon it. But I cannot take your curiosity amiss, and shall endeavor in a few words to gratify it. Here is my creed. I believe in one God, the creator of the universe. That he governs by his providence. That he ought to be worshipped. That the most acceptable service we render to him is doing good to his other children. That the soul of man is immortal, and will be treated with justice in another life respecting its conduct in this. These I take to be the fundamental points in all sound religion, and I regard them as you do in whatever sect I meet with them.
As to Jesus of Nazareth, my opinion of whom you particularly desire, I think his system of morals and his religion, as he left them to us, the best the world ever saw or is likely to see; but I apprehend it has received various corrupting changes, and I have, with most of the present dissenters in England, some doubts as to his divinity; though it is a question I do not dogmatize upon, having never studied it, and think it needless to busy myself with it now, when I expect soon an opportunity of knowing the truth with less trouble. I see no harm, however, in its being believed, if that belief has the good consequences, as probably it has, of making his doctrines more respected and more observed; especially as I do not perceive that the Supreme takes it amiss, by distinguishing the unbelievers in his government of the world with any peculiar marks of his displeasure.