Non AC heater box C60 to K20

[redtractor007]

Hi all. My non ac heater box for my 1977 k20 is junk and we have an old 70's c60 that is non ac. It seems the blower shroud on the engine side is the same. Would the heater core box inside the cab be the same as well? Or has anyone ever made the conversion. I have called local junk yards and they don't have one so I was curious if those boxes were the same. Thanks

 

[bucket]

I would assume it's the same... but I do not really know. I'd be very curious to what you find out though. I know the center of the firewall differs greatly from the pickups, along with the floor.