Thanks Guys, I checked out the numbers again on my drivers side door and they are copied correctly. The bottom line for me is that I loved the way my truck handled with the 4000 on it so I'll just stick to what I know works.
I have no plans to change trucks for the duration unless I strike gold.
I have found some comparable rigs but they are usually a little distance out of town. If that's what it takes, that's what I'll do. The fellow who bought my 4000 drove all the way from NM to here in Oregon to buy it from me..