your particular heater doesn't represent the entire class "Harrison heaters", which may be obsolete items, but are documented in proportion to their production and use, not "lost to the past" .... above you point out your heater was part of the military 'arctic kit' in a period when civilian vehicles and their parts were adapted to military purposes, and which adaptations were abandoned after 1945 in favor of improvements for public consumers - sorry, but your rare military Arctic specific heater appears to be one of the casualties of the war, maybe you should be asking some govt historians that know about the maintenance of military vehicles in WW2
or try the patent office -
here's one from the 30's - and
one from 1941, although I doubt anybody bothered patenting limited production military items and there were as many different heater versions as there were vehicle models pre-1950's
note from the article PDF Tim linked above: "
Prior to 1959, all heaters for General Motors cars were highly car-specific, requiring little or no common tooling for their manufacture. In 1959, a corporate-wide standardization program was undertaken to reduce tooling costs, make best use of the manufacturing facilities, minimize the number of service parts and simplify the operations of the assembly plants."
Bill
