Help cant get heater box out

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Richard B

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There is an AC exchanger cover on the firewall and it is covering the heater studs, and I can't get at the nuts. Do I have to totally remove, that is destroy ( it's very brittle), this schroud to get at my stud nuts out?
 

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Richard B

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The answer is it has to come out in pieces. If you don't want to disconnect the AC components. Well now it looks like the ones that are not diesels. I guess that will do.
 

75gmck25

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It’s been a long time since I replaced mine, but I don’t think the AC box had to come out. However there is one stud hidden by the inner fender. You need to unbolt the inner fender and pull it out of the way, or some folks manage to get a universal joint and socket in there. Attached is the page from my ‘75 repair manual. Steps 1-2 (not shown) are to disconnect and plug the heater hoses.

It's also a PIA to get the heater box back in, because you are pushing and compressing the firewall insulation, and at the same time trying to line up the bolts with holes in the firewall.
 

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Terry Wilkerson

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It’s been a long time since I replaced mine, but I don’t think the AC box had to come out. However there is one stud hidden by the inner fender. You need to unbolt the inner fender and pull it out of the way, or some folks manage to get a universal joint and socket in there. Attached is the page from my ‘75 repair manual. Steps 1-2 (not shown) are to disconnect and plug the heater hoses.

It's also a PIA to get the heater box back in, because you are pushing and compressing the firewall insulation, and at the same time trying to line up the bolts with holes in the firewall.
75gmc is right pull the inner finder well. It's not hard. Easier with the wheel off. Then you will see the hidden bolt.
 

Grit dog

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AC box stays in. Bottom nuts are hidden. All are on the firewall. But you can get em with enough extensions and a swivel. Heater box come out from the inside.
I left one of them off when I reassembled. Heater was tight and no fkin way I was getting it back on.
It’s pretty straightforward. Probably twice as fast the second time. Just take your time. Brute force and old heater boxes do not get along.
 

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