I have aquired a non AC blower and metal air box off of an 86 chevy fullsize pickup. It looks like it may work in place of the factory AC box on my 87 T/A with little to no modification other than drilling new mounting holes in the firewall for the new box to mount to.

Anybody ever tried this?

I got the blower and air box for free and it has a new motor on it. So I am out nothing if it doesn't work.

 

I was searching through my posts looking for other info and stumbled onto this post. I had forgotten to post a reply that I did do this conversion using the full size Chevy truck heater box and it worked very well.

I cut the Chevy truck heater box in half down the middle separating the blower section from the air outlet side that feeds into the firewall.

Then I took some aluminum sheeting and formed an extension so that I could stretch the heater box making it around 3 inches longer. I used rivets and epoxy to secure it all together.
I then made the hole for the blower speed resistors larger so that I could mount the firebird's speed control onto the truck's heater box and then the box when installed would be a direct plug in. Then I painted it matt black. Looked nice when done.


I used one of the original bolt holes on the firebird firewall and the rest had to be drilled and sheet metal screws used for the rest of the installation.

 

I think that anything you can get ahold of that will fill the hole will work I would say. But I made my own out of aluminum sheet.