Proper tools for removing axle nuts, etc. are readily available, cheap, will last through several trucks, do not uses chisel and hammer. Jack up subject axle end to keep oil from running out or drain it all, remove axle and hub, if you cannot see ebrake assembly, finish job. If bearing nuts are buggered by some previous mechanic, clean them up while you are at it.

Ed

'37 GMC T-18 w/ DD 4-53T, RTO-610, 6231 aux., '95 GMC running gear, full disc brakes, power steering, 22.5 wheels and tires.
'47 GMC 1 ton w/ 302, NP-540, 4wd, full width Blazer front axle.
'54 GMC 630 w/ 503 gasser, 5 speed, ex fire truck, shortened WB 4', install 8' bed.
'55 GMC 370 w/270, 420 4 speed, grain, dump bed truck from ND. Works OK.