[HWYSTR455]

Ok, lemme take a shot here.

Just so we're clear, is this an A/C or non-A/C car? It looks like an A/C car to me.

This is straight from memory, so my suggestion would be to look at an assembly guide or service manual. The pic I attached is for 69-70, but gives you an idea. I know 71-72 would be different part numbers. But...

The broken plate I believe is what for 69-70 is called the Bi-Level Baffle. Would imagine it would be called the same for 71-72.

The square seal thing is called a Adapter, Duct .It connect the box on the wall to the lap piece that mounts under the dash.

The diaphragm depends on where it came from, and if it was an A/C or not car.

Pretty sure the seal kits include the seal for the duct adapter, but some of the kits include a cheap foam flat cutout gasket that is a POS, not like the dense foam formed one from the factory. I say buy 2 kits, they are cheap, and that way you can double up on some to get a better seal.

If you can use duct tape or other ways to seal better than the factory did, vent velocity increases drastically. The defrost to box area is a great example, as is the side vent pieces. No one will ever see most of it anyway. Think of trying to suck soda through a cracked straw, and that will give you an idea of how drastic even small fixes can make.

Classic Auto Air in Florida has and/or can get quality replacement seals and some hard to find OE parts. They also restore heater boxes, at a reasonable cost, it may be worth a phone call. I know they did my evap box for the 442, and it came out mint. It was totally worth the cost, it's wasn't a bend-over-backwards type cost.

Take a pic of the box and post.

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