Here's the front hub/axle shaft of my 4x4 F250 with wheel, all the brakes, hub and do-dars removed
From this point - how do I get the old seal out and the new one in ?

 

Did you decide not to use the stands and used blocks of wood instead?

Hope someone comes along soon with some info to pull the seal. I would guess just pull on the axle shaft (you don't really have to worry about messing up the old seal anyway), but I could be wrong.

 

The axle stands are on the wood blocks to give extra height.

The axle shaft is still attached to the u joints which is in-turn attached to the rest of the shaft into the (as yet) unopened diff case

 

You need to pry the axle out now. Usually I use a big pry bar in between the axle, where the U-joint is, and the housing. Sometimes they take a lot of effort to get them out.
To install the new seal you'll need a special seal driver. I'm not sure who else besides your dealer's shop will have that. You need it first to install the seal onto the axle and then to install the seal/axle into the knuckle.
Clean out the knuckle really well before you install it all again. I use a ball hone to clean it out if it's rusty.

 

so does the drive shaft have to come out of the outer axle tube (towards me as looking at the first photo in thread)? Do I have to open up the diff case ? The housing is still attached to the steering rods and ball joints.

Should all this be off the truck as I dont see how the u joints can pass through the knuckle -

HELP what have I got'n into ?

 

Yes the whole thing come through...look here
https://www.ford-trucks.com/contents...20Installation

Also you are going to need a special tool to hammer on the new seal...The inner dust seal is not a big deal.....Get back to me if you have any problems..

 

I have been following the page on the dieselstop.com (ball joint replacement), to help me replace the passenger side main seal on the front axle of my 200 F250 SD V10 6.8L. I followed it word for word. However on reaching the end of the job I find the axle on that side is very difficult to rotate, I can barely turn it at all by hand. Rotating the drive shaft by hand causes the divers side axle to turn quite freely but the passenger side stays still (I have the stock diff). Any thoughts ?

(I took the axle to my local Ford on Saturday to fit the new seal and the nice man fitted it for free. He even said I could have just borrowed the tool, taken it home and done it myself if I had wanted. Great guys !)

 

mine was tight also...they loosen up.