Refurbishing My Heater Box

I have removed under hood heater box as well as the inner box with the heater core in it . Not being an HVAC expert , I have a few questions on some of the components . . When I removed the outer there I a thin strand of wire that appears soddered to the firewall but not connected to anything anything ( see picture ) Another question is the correct color of the exterior box . Mine is a gray plastic that looks like it never was painted ( second picture ) Was reading it should be satin black

 

What about the one under hood box ? It’s a gun metal gray plastic with white “ speckles “ in it .

 

I used clear on both sides when I did mine.

 

Thanks, are there seals on both boxes and who sells if anybody a kit with all the seals ?

 

I used 3m caulking strips, blue box at oriellys or autozone

 

The original under hood box cleaned up and ready to install . I’m guessing should bolt/seal this one first before installing the inside heater core box. Got the firewall looking good again too

 

Just noticed after mounting inner airbox the large door on the right is not sealing fully when it is in the closed position . All of little control arms on the top of the box are moving freely. I can push the door closed but it pops open 1/2”. Just lubed the moving parts ?

 

Does anyone make a flexible connector hose that connects the defroster duct to the main duct on the heater box ?

 

It is rectangular it seals the plastic defroster duct to the metal defroster vent 4-5”” X 2”