They don't have much impact on each other.
The inspection won't care about a 2" BL, ...only an SL and tire height, typically, only if they are above that state's guidelines.
If its hard to find enough time to do both...and inspection is looming, its actually better to knock out the BL first.
It makes doing the SL a little easier, and, won't mess up the inspection.
A BL can take as little as a few hours to all day depending upon your skills/help. Most of the SL's are all day minimum, two days average.
Its VERY ambitious to try to do a SL/BL on the same weekend...it assumes no murphy factors, and good help, etc. Its possible, but, if you have the opportunity to split them up, safer to schedule separately.

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- 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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