It is in fact serial 70-666, code TR-666 but painted with fake serial 70606 and code TR-606.

Providing shade for spectators waiting for the airshow. Last unit is quoted by Forgotten Jets as the 87th FIS at Lockbourne AFB in September 1968, though that was not an Ohio ANG unit. She spent some time preserved at Lockbourne AFB before coming to Vinton County for display (though the same source quotes time at the USAF Museum in Dayton as well.) Weirdly enough, the next T-33 in serial sequence (57-0587) is displayed in Flagler, Colorado, where I photographed her 15 years prior.