If you go custom anything is possible. However, the design of the front IFS system does not allow more that 2.5-2.75" lift. In order to go higher, you would need to either look at one of the option posted above or have it custom built.
Once you start going higher than 2.5-2.75", you start introducing extreme angles into the CV's, and steering arms. Once you start dropping the Front Diff lower than the current Diff drops available, you start having conflicts between the front drive shaft and front Sway Bar and again start creating extreme angle for the steering rack and rod ends. The list goes on. There is no aftermarket support/products available to get around this with out going with one of the two options posted above or a true custom build.
Lots to read on the topic here with a little time and searching. It comes up at least once a year or more. Good luck with your research!