Jake,
I would think that most reading my post would infer that I wanted a heater that was a factory original for either the Henry J or Darrin.
And just to be totally clear for your benefit, a KAISER DARRIN, not a Packard, nor any other the myriads of Howard "Dutch" Darrin cars that have been made.
Although your answer may be useful to the public in general, it was not for my query!
But, thanks anyway.