Can an upper damper coexist with an insert?

[Annapolitan]

First time poster.

We have a masonry wood-burning fireplace that has:
1. a lower damper right above the firebox with a lever
2. An upper damper on top of brick chimney with a long cable and chain that you pull to close
3. A little metal opening at the back that you open to feed the fire with fresh air from outside and close when not in use
5. A small trap door to an ash pit below.

We’d like to put an insert (leaning Towards a gas insert but am also considering wood) into the fireplace but have the following questions.

1. If we do gas, both dampers have to go (or be clamped/welded open) due to building code?
2. Is there a way to preserve the upper damper if we do an insert, either wood or gas? I don’t see how we would still access the chain (pull to close damper) with an insert in there.
3. Going in a completely different direction and probably very naively, are there any products that can put a nearly air-tight door/front facade with tempered glass on the front of a fireplace? To make the fireplace operate a little more like a woodstove? Maybe even with the ability to regulate the air intake?

 

[wooduser]

3. Going in a completely different direction and probably very naively, are there any products that can put a nearly air-tight door/front facade with tempered glass on the front of a fireplace? To make the fireplace operate a little more like a woodstove? Maybe even with the ability to regulate the air intake?

There are lots of manufacturers of custom fireplace doors. They aren't going to turn you fireplace into a wood stove by any means, but they allow more control over the vast quantities of heated room air that are customarily sucked up the chimney by a fireplace.

 

[Heatsource]

properly installed a wood or gas insert and you wont need a damper anywhere in the system.