You are asking how high to set it, so sounds like you are doing it yourself.
If so pick a height, and then take your tools with you, if it is off too much, then can readjust on site. If off by just a bit, tow it home and correct it there.
Russ & Paula & Beagles Belle
2016 Ram Laramie 3500 DRW 6.7 CTD Aisin 3.73's
2005 Copper Canyon 293 FWSLS 32’ GVWR 12,360
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