Stock 1965 F-250 Dana 60 Torque & HP Limits?

[chris401]

My Dana 60 came with the acorn spacers behind the axle shaft nuts. It isn't nor will be a hot rod however the end goal for the 430/462 MEL is over 500 lbs of torque @ 2300rpm with HP 350 - 400. 14,000 lbs will likely be the bulk of the heaviest weigh I tow. What are your experiences with our stock 60's?
Thanks