First picture shows approximate location of the studs sticking through the firewall (arrows).
Second picture shows actual studs on removed heater box. Upper left circle shows heater hose connectors. Please note- the heater hoses MUST be removed, they will not come through the firewall. (Ask me how I know). The white arrow is the "heater blend actuator". This is the new one. Should give you an idea of how tight to the firewall it really is.
The cable from the dash control that operates the heat flapper must also be disconnected (picture 3).
