Talk to any classical Unitarian and they will say something along the line of Jefferson's statement of being a sect unto himself. The Jefferson Bible is classic Unitarianism as much as such a thing exists.
I'll charitably grant that the Jefferson Bible was "as much Unitarian as such a thing exists". As far as his personal beliefs went, I will charitably grant Jefferson to the Unitarians, even though he NEVER actually claimed that church mambership for himself.
But Jefferson's kind words for the Unitarians in 1822 does absolutely NOTHING to support the idea that he was "proseltyzing for the Unitarians" in the Virginia Religious Freedom Statute of 1786 (which was as much the creation of the Calvinist James Madison as it was the Confused Thomas Jefferson). Good grief, man, that is THIRTY-SIX years of a man's life!! Thirty-six years ago I was not yet a Calvinist; heck, I was not even born.
In 1822, Jefferson may have, at the end of his life, turned out to be a "unitarian" (or at least, somewhere in their relative vicinity). But in 1786, he was certainly not "proselytizing for the Unitarians". The idea is absurd.