I just looked at the cars and found my Ford has a gap between the two heat exchangers.
(refrigerant & coolant coils)
That allows me to just drop a sheet of Coroplas between the two.
Just like dropping a sheet of paper into a file folder.
It's not real cold yet, so I'm starting off with a 30% block.
And will select coolant temp on the SG2.
'C' upper intake:
I noticed a small air-intake duct on the left (passenger) side.
Inside the engine compartment, it exits right in front of the air-intake for the ICE air filter.
It seems to me, the duct is designed to allow cold air to flow around the coils and directly into the ICE air input.
It's a bypass air channel. Should it be left open?