2004 aveo vibration problem

i have an 04 aveo with 90k and never had rear brakes done, the problem is the left rear tire was locked up, after doing some research i determined that the bearing was locked up. When i took the tire off i noticed it has a one piece drum and hub, so i managed to get the drum and hub off, of course the shoes were no good.

I could not find a one piece drum and hub assembly for this car only either the hub or the drum sold separately.
I installed new shoes and a spring kit.
Bought a new hub with bearing in them and new drum.
Put everything back together and now the rear vibrates when i apply the brakes over 20mph
I tested using emergency brake and vibrates from the back.
The hub fit perfect over the spindle and the lock down nut tightened up nicely (spins perfectly)
The drum went over hub and I even used the two little phillips lock down screws as well.

My question is Why is it vibrating when brakes applied??

I dont know if the owner had the same problem before i changed the drum and hub?

I replaced shoes, springs, drums and hubs on both sides.
Any help would be appreciated
thanks

With all new hardware, the only thing i can think of is the new drums could be out of round. Even if they are new, they could have been dropped, or mismachined.

the other things are possible, but if installed correctly with new hardware, it is unlikely.

Try swapping the wheel to the other side and see if the vibration moves, the tire is probably messed up from being locked up. If it stays the same I'd suspect that the spindle is to blame.

Thanks for the input, I will try to swap tires and see if that helps?
I was suspecting the spindle but I didnt want to drag that deep into the car.