Except for the part where you've posited that the basis of conservative thought is the source of human rights, rather than the fact of their existence.
The Source and existence of our rights are an unbreakably linked...You can't separate the two.
Certainly, John Adams, Sam Adams, John Hancock, John Morton, Robert Treat Paine, Benjamin Rush, Roger Sherman, Richard Stockton, John Witherspoon and other signers thought so.
Can you name a founder that did not attribute the existence of our rights to God (with primary source documentation)?