The vibration in your transfer case shifter could be traveling up your running gear from the gears. The speedo will change similar to changing tire diameter becuase it is directly proportional to revolutions in the transfer case. The steering and brakes could be a result of not getting the front end put back together right. I assume your vehicle is IFS. Alot of stuff can go ary in IFS alignment. You mentioned the gears were set up without instraments, was a torque wrench used on re assemblying the front end?

Cisco