Don't forget to check the spring hangars. There may be another hole available to raise the FW, usually about 2". I tow about 2-3" nose high, depending on load, and don't worry about it. The nearly 8" bed clearance is needed so I can get into our usual boondock site. I've thought about a flip on my FW, but it's not going to be much longer in my possession, so am not going to worry about it. If the axle is already above the spring and the springs are in the bottom hole, there are really 2 other options. A Correct Track alignment system gives about 2", but for about the same money you could have a sub-frame built to raise the FW to whatever point it needs to be to get level. Biggest issue with this is that any mods would likely void the frame warranty.
Lyle