340 Motor with 360 heads?

The "360" on the head doesn't make them 360 heads. You'll need to find the casting number on the head to find out what heads they are.

Also, the 340 and 360 shared the same casting numbers on the head. When the 360 cam out, they used 1.88 intake valves with the same casting numbers (head) as the 340.

Auto Zone has drums and discs, pads and shoes.

When you say the balancer was drilled out, it leeds one to assume you mean the balancer has holes drilled through it.