wd hitch and 2 1/2 to 2 inch reciever

A sleeve is a sleeve . How much difference could it make . Warnings like that are to prevent law suits ! IMHO

I suggest you use the WD system and just don't assume you don't need it. Better to have it. You're on the right track. Go with your plan and be safe!

Sounds like you purchased your truck used, in which case it makes sense the sleeve is missing. I would not advise using the sleeve that you purchased if it says do not use with WD. Go to your local Ford Dealership and buy the correct one. You will need it again in the future, guarantee it!

I would probably not use the WDH, like use the adapter with the shank, but not the WD bars. You have plenty of truck weight and suspension where losing 250 pounds off the front axle will be unnoticeable.

I am surprised your ford didn't come with a reducing sleeve. Anyways, you would probably be safe, but maybe look for another sleeve that doesn't say that. There is a good amount to offer at eTrailer.com. Do you even need a WDH with this trailer? You do have a 1 ton and how big is this trailer?