I don't have a Que, but since no one else has responded, I'll take a stab.
I have replaced all 3 vent lids on the 2499 and like you puzzled a bit over the differences in styles. I hope the following links will help you sort it out.
I'm assuming the Que has the typical 14" vent and then Sunline likely used the same style lid as on the other trailers. I would recommend you get this somewhat pricier lid--which I did--in hopes of it lasting longer:
http://www.campingworld.com/shopping...vent-lids/1444
I would also treat the inside and outside of the new lid with 303 prior to attaching it.
Here's a good link for determining the lid style. You obviously don't have the pre-95 one and the Jensen attaches with a pin. I think you need the top one "new style 95 and up Elixir". Click on the links or the thumbnail to see a large photo showing the hinge type of each style.
http://www.tjtrailers.com/store/vent...vent-lids.html
...or...
http://www.pplmotorhomes.com/parts/rv-vents/31-4164.htm
If you have the same lid I have, you'll see what looks like a small coil or spiral of metal at the hinge area. This is twisted with a needle nose plier and is all that holds the lid on. A metal connector on the lid mates with a metal connector on the base. Use the needle nose to grab the inner piece and twist it like the original and make sure that does in fact keep the lid in place. It looks klutzy, but I had no trouble slightly uncoiling this piece to slide the lid off and then attach the new one. All 3 were very easy and quick to replace.
Hope this helps.
Henry
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