A PW can be leveled easily, just not as cheaply. Keep in mind the control arms are the same as the regular 2500's, but you are already lifted 2". Hence the control arms are already pushed to the angle that your last 2500 was after the installation of the spacers. Pushing it another 2-2.5" will put the arms at such an angle that you will have issues with alignment and ride quality.
Cheapest way I have found to get it done and still maintain a quality alignment and ride quality is one of the below.
Buy ONLY the front 4" lift parts for a 2500 Gas HD. This will usually include longer control arms, springs, a drop pitman arm, a drop bracket for track bar, longer links, etc. This will give you +2" on a PW and will include all the little pieces needed to make the front end work.
On the cheaper side buy a set of adjustable lower control arms and your 2" spacers. For on road it will work fine, but you will pick up a lot of bump steer off road and can have some binding issues during full flex and compression of the suspension.
Just Got it, Give me time!