When I got my F250 the front leaves were sagged - very common with the usual & obvious signs - front springs bending upward in the middle and front sway bar ends poking down.
I rectified this by importing a Tuff Country Levelling Kit. Leaf packs of 5 leaves each are added under the stock springs and bolted together with the supplied longer U-bolts.
The results was a "4 lift over the sagged height & and increase from 50mm or front suspension travel to 100mm of suspension travel. To equalize I swapped out the standard rear blocks and put in 3" blocks, and in order to soften the ride I also took out the short fat bottom leaf from each side at the back.
After all this the truck never looked quite right because the front looked more lifted than the rear.
So I'm swinging spanners last night getting warmed up, and figure it is time to 'adjust' the front suspension down a bit. 4 hours later the truck is back together after taking the smallest 2 leaves out of each of the front spring-packs - still leaving 5 leaves each side, & still having 100mm of front suspension travel.
All round the truck now the gap between the top of the tyre and the top of the wheel arch 26cms.
Finally, truck LEVELLED for the first time.
While I'm keen I'm planning to do the G2WW change over this w/e.