Blower motor fan depth?
 

Im rebuilding the heater components for my 1980 Chevy k20 (w/o AC). I ordered a replacement blower motor, Four Seasons 35334 , which is supposed to fit my truck. Upon receiving it, the mounting flange fits up fine to my blower housing but the fan sticks out about an inch. I did some more searching and came across Four Seasons 35345 which appears to have a fan that is less deep. Both models are listed as "fits 1980 chevy k20".

What gives? Are there 2 different sizes of housings for these trucks? Why is it not clear which one is correct?

Re: Blower motor fan depth?
 

Don't know for sure but maybe a difference between standard heater(Florida) and heavy duty heater(Canada)? I know the 66 PU my dad bought new had a SPID listing for "heavy duty heater". It was otherwise a very basic truck.

Re: Blower motor fan depth?
 

I think you are correct. I found this site that lists 2 options for a refurbished blower housing. http://thepartguy.com/heaterboxCHEVY...eBody73-87Heat

The standard 3 prong resistor housing and a heavy duty one with 4 prongs. Must be deeper to accommodate a deeper blower motor. Little strange that there is almost zero info on the differences out there!