IMO, your bigger issue here is bed rail clearance. If you have been getting by with 4-5"s of clearance, then you are being careful.
I would not be too concerned about being 2-3"s nose high, over the entire length of your FW. Yes it will transfer a little more weight on the rear axle, that could cause an issue, if your tires are just barely adequate for the weight they are carrying.
We all know level towing is best for FWs. I think I have noticed more folks towing 2-3 inches nose high, than ones that are level.
Bottom line, if you are getting by with bed rail clearance, have capable tires, and are considering an upcoming trade, I'd just leave it alone.
Jerry