Need advice on a 2wd lift kit.

The common way to get 6" of lift would be a spindle kit.
You can also go to a body lift on top of what you have now.
If you just want a 5"-6" and not concern with performance this would be the cheapest.
If you are concern about performance(doesn't sound like you are) you can have custom arms , hoops built, coilovers, leaf pack etc, a lot more expensive.
Best way or cheapest?

First of all,I really don't think much of body lifts.
Mainly because it does nothing to improve the performance of your suspension. It is like they state , a body lift and not a suspension lift.
A 2" body lift plus with the spindle lift will get you at your desired height.
I don't know much about body lifts but the better kits have ways of dealing with most everything necessary I do believe.
Maybe someone who done a body lift can better explain.