Professionally doing this types of work for over 30 years, for the DOT.
Pack them bearings until grease pushes out the opposite side from which You are packing the grease into.
Smear a light coating into the hub and onto the inner races. Just enough to prevent hubs from rusting. Smear the spindles with a nice light coating of grease and the seal area too.
Install the back bearing into the hub and drive in the seal.
Install the hub/drum onto the spindle and shove on the outer bearing and screw on the nut.
Tighten down the nut, rotating the hub/drum, tighten it down real tight while spinning the hub to force the excess grease from the bearings. NOW BACK OFF THAT NUT. Turn it down to about finger tight. Using fingers You will not get it too tight that it will burn out the bearings. If there is a cotter key, back the nut off until a slot in the nut aligns with the hole in the spindle. Never tighten the nut to make it align. You want a very slight movement between the hub and the spindle.
If there is an outer nut, leave the inner nut slightly loose. Install the outer nut so it is to torque spec. Now grab the hub/drum and pull out, push in, is there movement between spindle and hub ? Yes, back off outer nut, tighten inner nut slightly, repeat until a very slight bit of movement can be felt.
If the outer nut tightens the inner nut too much so no slack is felt, then slightly back off the in er nut and repeat the steps.