Shayne k, I think you are not looking at the correct numbers for your truck..
When you say your truck has a "Towing capacity of 7500 lbs", is this what the "GVWR" is on the trucks door jamb sticker? If so, that's not it's "towing capacity"... ;)
The reason I think this is because my old 1997 F150 had a "tow capacity" of #7700... But, the trucks GVWR was only #6250..
If the trailers "GVWR" is #7490 as you state and it's "dry weight" is #5240, then you have #2250 of stuff you can add to the trailer.. That's not too bad and in all reality, you'll likely be a loaded weight < #7000..
I also don't think you are reading the "Hitch Weight Capacity" of the truck either... That "#600" figure is if you don't use a WD hitch setup.. When you actually use a WD hitch setup, it's likely it's rated for at least #1100..
Without knowing any of these things for sure, since you are just quoting numbers you see plastered all over the place, I could be wrong of course, but it just sounds a bit like "noob" numbers... :) Now, I mean that in purely "fireside" talk and not busting your ba@@s at all.. :)
Just trying to make sure you are looking at the right stickers for the right things... ;)
Mitch