See Ranger 3000 Guide for detailed scale specific set-up instructions with pictures or follow below
Remove the small red circle (weigh below access) on the bottom of the scale and screw the hook in.
Remove the large rectangle cover and plug in the RS232 cable to it. You can remove the tab for the middle cord slot from the rectangle and place that back on the scale.
Place the scale on top of the rack with the hook hanging down.
Update the settings within the menu by watching this video or following below

Press and hold the menu button until the word Menu flashes on the screen, then let go. You should see C.A.L. on the display.
Click the Print/No button 5 times until you see P.r.I.n.t. on the display
Click On/Zero/Yes
Click the Print/No button 2 times until you see A.PrInt on the display
Click On/Zero/Yes
Click the Print/No button 2 times until you see IntEr on the display
Click the On/Zero/Yes button 2 times
Click the Menu button again to exit the menu

Assembing Rack