You pretty much described doing a PML in your post...adjust the t-bars to raise the front, add shackles to lift the butt, go get a wheel alignment...that's a PML.
You can do a 1.5" PML easily.
BTW - the 1" shackles are just an inch longer than the stock ones, so they only give you about 0.5" of lift, not an inch.
What you really want are ones that are 3" longer than stock, to give you 1.5" of total lift...and also within the t-bar adjustment range, to match.
If you get larger tires, when you stuff them, they will hit unless you get a body lift...so the body lift adds up travel room/preserves articulation.
The stock shocks will reach on level ground after the PML, but, you can dramatically improve rear travel with longer ones, like the extended length Bilsteins, 5100's typically, say 10-20% stiffer than stock.
The front travel won't be improved with new shocks...the IFS can't droop past their limits anyway...and the angle the shocks are at means that a 1/4" of shock travel gives around an inch of wheel travel...so the front stocks reach either way.
The ride and handling get much better with new shocks all around though.
So - just for articulation...just replace the rear shocks with longer ones...and keep the stockers up front.
For better ON ROAD performance/ride...replace all 4.
BTW - the first mods should be getting rid of the stock step rails, mud flaps and rear sway bar (Keep the front sway bar...that one makes a difference).
Hope that helps a bit.
_________________________
- TJ
2001 Xterra '03 VG33, SE 5 spd, 305/70/16's, Revolvers, UBSkidderz, Doubled AAL's, 3"SL/2"BL, winch/bumpers, skids, sliders, OBA, Snorkel, pine stripes....
Friends don't let friends drive stock.
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