I got my heater blowers kicking butt again! Yeah.
This is the problem relay. It is in the off, or open position.
This is powered on, an closed. If the contacts don't close when the power to the engine compartment fan is running, the footwell booster blowers will not run. I guess the first run at it trying to clean the fuses and connectors was not good enough. You can see the glass tube with the wide coil of wire around it. That is the reed relay that senses the power on at the engine compartment fan. If the engine compartment fan is not running, it will not allow the footwell blowers to run.
When I first took the relay off the harness I saw this corrosion, and assumed that was the problem. I cleaned it but the fans would not come on. I can only assume after a dozen installations and removals of the box, something finally connected. I also spent more time cleaning the three fuses on the side of the engine compartment.
Bottom line I have the super duper heater of the G body heating system working at 100%. And as a bonus, I added the fuses to the two footwell blowers that Porsche left off until 1986. Fuses were not a strong point for Porsche in that era.