A tip on thick radiators.
I used 2 AC evaporator cores out of Lincoln town cars.
I did not seal the grooves at the end of the radiators but just allowed the
aluminum air ducts to ride onthe edges leaving small air passages at each
section.
The result was 240 Deg. F. coolant temp. in climb.
I then sealed these openings with RTV and in a full power climb to 3000 ft. i
saw 180 Deg. F. coolant temps.
The thick radiators MUST have sufficient stratic pressure to work properly.

Hank H.