I have a eaton posi with 373's in my truck maybe I should let you drive it for a few days so you can have a feel for it & see how it handles then see if thats what you want.. But then again if you do you might want more then just a posi unit.
"How bout BigBlock" That truck would look sweet & sound even better with a BigBlock now that it's not your daily driver. Also You might want to buy some gears well your at it too so you only have to open the Diff once.