No need to change anything except springs and maybe shock absorbers.
Shock absorbers need to be working within their range of movement, meaning not bottoming out or topping out on full droop.
If you have castor adjustment (plates or off-center bushings) then these will probably not be needed at 2".
3" is borderline for castor adjustment and 4" upward is almost certainly needed.
The panhard's are a "suck it and see" situation. I went from standard (sagged) height to new +4" and I haven't changed the panhards. Others have complained of the axles shifting sideways up to an inch, so then it may be necessary to change them (lengthen them). What does seem to be the case is that adjustable panhards are pretty much a waste of money because you want them at the right length, not necessarily adjustable. Once the right length, that's it, fixed.