Advise on Purchasing a TT

Spend $15 at a CAT scale with current trailer to understand where you stand with respect to all your truck's ratings. I suspect that 9800 pounds dry would put your Excursion over at least one of it's rating,s and probably a few of them including tow rating/GCWR.

I know it's dissapointing but better safe then sorry

Highland Ridge is coming out with a new line up for 2018. You may find a model that works better for you.
http://www.rvbusiness.com/2017/08/highland-ridge-rolling-out-revamped-lineup/

Thanks for the great advise. I'll hold off on the TT until I can get a Truck that can tow it. Really love my Excursion, so too bad it can't tow another 1000lb more.

Scott G pretty well summed it up. You will most likely be over your TV's capacity.

If you really need to know, rent a similar unit for a week or so on the road and see for yourself. You can also run over the CAT scales for the real numbers.

Yes many people over load their TVs and never know it. They just adjust to the acceleration and braking and assume it is normal. The end result is increase wear and tear on the TV.

A really bad TV and TT mismatch is obvious.

"Just curious if I would still be okay"

You'll be fine... in fact get the even bigger one. Everybody knows you can tote twice as much as Ford says and you'll never load up on water, bikes, bbqs and other stuff.

You will be well over your weight rating and not by just a little. Being within a thousand pounds with a dry RV is begging for failure.
This is a mistake we only make once in life. Mine was many years ago so I speak from experience.

Here's a little secret I learned.. A TT can weigh more than it's dry weight even when it's still dry and empty.
The reason is because the "dry weight" does not always include the toungue weight.
My TT's GVWR is 10,400# and the weight on the axles is 9300# (nearly 1500# more than is advertised...) Great eh? I have 1100# of capacity!
That doesn't count the 1400# the tongue weighs!! (which btw is almost 500# more than it supposed to weigh.)
So my trailer actually weighs 10,700# or 500# over it's stated GVWR and that's the real load on the truck.

Long story short, I can guaranty you will be over by at least 1000# and maybe much more.

What you need to do is look at the sticker by the drivers door and find your payload capacity.
gross vehicle weight minus curb weight equals payload.
Now add the weight of all passengers and gear you plan to place in vehicle plus 15% 0f trailer weight (Hitch weight or tongue weight)
MY guess is you are WAY over.
NB:
I looked up the specs and supposedly your truck weighs about 6800 if 4x2 more if 4x4with a gvwr of 8600. That gives you a payload of 1800 lbs. The trailer hitch weight is about 1400 lbs leaving 400 lbs for you, wife, pets, tools and whatever else you plan to carry in the excursion.

https://www.ford-trucks.com/specs/2004-2/2004-ford-excursion-specifications/

So what happens if I would creep over the weight a little? Has anyone creeped over a bit? Just curious if I would still be okay or if I should walk away from this deal. I have the largest SUV on the market and don't want to go away from something that gives me this much room.

Are you aware, your max towing capacity is going down, as is your available payload, while you are loading people, pets and cargo into the tow vehicle, and your weight distributing hitch takes away about 100 lbs?

Average load (dishes, bedding, camp chairs and gear, BBQ, pots and pans, groceries, and water) is 800 - 1000 lbs.

While your tow capacity is creeping down towards 10,000 lbs, the trailer will be creeping up towards 11,000.

You'll be on the edge, if not over weight.