[drolston]

First, ditto Lawson Cox; the 36 flathead fan does not move much air at idle. I bet it will cool right down if you drive it. The radiator is working pretty well, as it is dropping the water temp by 20 - 30 degrees from top to bottom. But it may be lacking enough cooling area due to blocked tubes on the inside and/or bent-over fins on the outside. Bent fins can be straightened up using a metal nail file. Buy or borrow a video borescope to get inside the top tank to look for crud, or tubes that do not drain when the radiator is drained.

Retarded timing will aggravate overheating. Be sure the points are set perfectly, then advance the timing until it pings when accelerating hard in second gear; then back off one mark.