Hey Old Sub!
SO, If my truck has a 'warmed over' 350, th350, and the jag rearend with 10" tires- I should be ok, huh?

Shayne
I have a Dana 44 with a warm 350, 4-speed (4+3 actually), 10-inch tires and haven't broken it yet. I drive it most days and at 110,000 miles the diff isn't my biggest worry. However most the time I drive it just like I would my wife's Jetta, treating it like transporation on a public road, not a race car on a track.
And someone said 500 horse, and at that level I would not be nearly as confident it would last.
There is no trailer hitch on the back of my 'vette and its rare to see a Corvette or a Jag or any performance car with IRS pulling a trailer.
It really comes down to how you are going to drive it. I'll stand by what I said earlier, the Jag spec Dana is not as stout as something like a nine-inch Ford and if abused it will break.
But I'm sure you'll be okay. You'll never abuse it, right! (I have four Dana's and one is broken...)