here is a 64-66 deluxe heater motor and one out of a 87 gmc p/u. There may be about 1/16" variance between the 2 in depth
perhaps the one out of the 88 suburban is for a higher capacity, due to the larger space and the demand for better heating in newer vehicles then there was then. then it was all for one and one for all(almost)
ron
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rondavid at 2011-10-12