The heater box I purchased from ACS has the heat exit the box out the opposite side of the inlet while it is not in use. I didnt like the idea of the hot air blowing directly on my solenoids so I made a shroud to cover the exhaust of the box. I then cut the hole in the firewall and fit the box to the firewall near the solenoids. See photos. The nuts in the photo are just to hold it in place temporarily.
