Go for it!
I think the steering box is the same on both a 1/2-ton and 1-ton so it should be easy to adapt the steerng related parts.
I don't know about the difference in spring width, but I'd try to make the 1/2-ton axle fit the 1-ton springs perhaps by moving the u-bolt holes or perhaps drilling them out larger.
Springs, shocks, steering and brakes are the only places the axle touches the truck, and springs the only one that might be a challenge.
The 1/2-ton axle is not as strong as the 1-ton so your max load capacity will be reduced by that change.
The swap to disk brakes will probably improve your braking, but not improve it to current 1-ton specs. Also the disk brake conversions, either 5-lug or 6-lug will mean using wheels that are likely not 1-ton load rated.
If you won't be hauling 1-ton loads I don't see those issues as significant. But remember you no will no longer really have the original 8800 weight rating. If that doesn't matter go for it!
