OK I have done a lot to this truck but this is a new one to me and I ma looking for advice. My diff is leaking BAD where the drive shaft connects. This is a truck I will have for life so I like to fix things right. What do you experts recomend I do? whole new rear end ( if so whats the best?), just new gears and seals? or just replace this seal? Thanks for any help. Here is a pic of my truck.

 

Most leaks can be fixed easily with just a new gasket/seal. Others however are so bad that it's just easier to swap.

 

While this is not the recommended way doing it......
Unbolt the drive shaft and ensure there is not excessive play in the pinion (indication of bearing wear / failure); mark the exact position of the nut on the pinion using a small chisel, remove the nut - pull seal and clean up, (scotch bright or 600grit on the pinion yoke where the seal runs to ensure smooth and rust free) Install new seal. Slide yoke on pinion, use RED Loctite and reinstall the nut and tighten back to the same exact place.

I have fixed a number of vehicles this way - both GM & Ford.

ToddsSS
Benton, AR

 

That is a beautiful truck! I can see why you want to keep that for life! I have the same colors on mine. Yours is an inspiration to know that mine could look that good some day!