Technical 57 Chevy 3600 pinion nut torque

Hi all, I am replacing the pinion seal on my 57 3/4 ton and can't seem to find a torque spec on the pinion nut. If anyone could help me out I would really appreciate it.

 

http://chevy.oldcarmanualproject.com/shop/1955truck2/55ctsm0417.htm

160-280 ft lbs

 

You are awesome! Thanks a ton!

 

Those pinion bearings usually loosen from normal wear over the years. The old timers taught me to tighten the yoke until backlash is gone, but not preload them.