I finished the Imperial Questline a while back, but everytime I go into the Palace in Windhelm, Ulfric is still there. A naked, dead, guy is not all that decorative, even laid on his back with his arms crossed. None of the exiled Jarls seems to notice him, they're too busy kvetching about their exile in a nice cozy palace with plenty of food....

So is there a way to make him go away? (I have the USkP in, but apparently it doesn't fix this for me.)

Use the ritual stone it has no level limit and should last long enough for you to dispose of elsewhere.

You can move the body to a less visible location by carrying him away.

Or you can activate Ritual Stone near Whiterun and make him your Thrall and leave him somewhere deep on the dungeon. He can be an entertaining companion, I heard. He can shout.

I had the same problem with Galmar so I dragged him behind the throne.

throw his body up on the dinner table for all to see and remember to not make his mistake...this coming from a rebel supporter who's not an ulfric fan

Galmar is at least capped at level 40 so he's always subject to Dead Thrall.

I dragged him and Galmar into the map room and never set foot there again.