Installation Issues / Questions

I've been lurking here for some time but now have a question that I need to bounce up against the pros.

Situation - we have a masonry fireplace and are going to put an insert into it. We decided on a Quad 3100i (with many thanks to this site....) and paid for the unit several months ago. Fireplace was originally surrounded by tongue and groove pine(!). We had the area around the fireplace tiled with ceramic tile and the hearth extension brought out to meet code. Being that the firebox is 8" off the floor we had our tile guy pour a solid piece of concrete to match the footprint of the unit as it sticks out into the room and then tile it. So - in summary we have an investment in the fireaplace and are pretty much committed to it as the whole thing was built specific to the unit.

When they came out to install the unit, I was told that they couldn't clear then lintel with the ventpipe. The opening of the fireplace is 37.5" wide by 25.5" high - so it's a big firebox. The lintel is another several inches further up inside the smoke chamber. The house is a 1953 rambler.

As near as I can determine, lintel clearance is tight - but there has got to be a way to do this. Is there another flue connection option beyond the rotatable elbow that they were going to use? If so, what is a reasonable amount to pay for it? I realize there is no way to completely understand the situation without seeing it, but I can't believe for a minute that I am the first person who has had this problem.... THe thing that burns (ha!) at me a bit is that we had both the salesman (yeah, sales guy I know- but he was knoweldgable) and the install foreman out to check everything out, measure etc before we sunk all the money into the fireplace work. Both of them said "no problem".

Any thoughts or recommendations of course of action?

Thanks in advance!

Not the damper throat - the lintel. It sits about 3" up, just inside the top of the firebox and is about 3" square - give or take. I gather it is used to support the chimney itself. There is approx 8-10" clearance from the top of the stove to the bottom of the lintel. It intrudes less than 1" into the space needed for the flue pipe - but that excludes the use of an elbow given the intrusion. If the insert were 1-2" further back into the fireplace it wouldn't be an issue - there is a ton of space in the box (sides, back AND top). Chimney itself is 12x12 (or so) clay tiles, so not an issue at all. The challenge seems to be the connection between the top of the insert and the liner and the clearance needed to make it happen.