Step 1: Get to the tank at the church a ride it [Cost:500].

Step 2: When you ride around you will see a little wooden tower to your right near a bridge jump off and get the first part.

Step 3:[Get back on tank]Go arond again and jump on a broken walkway at the dig site go under ground and you have part 2.

Step 4:[Get back on tank]Go all the way around and you will see the church and there is an area where you can jump off to the right of the church go inside and you have the last peice.

Music Purple disc for me is in the building at genertor 2.

The portal is near generator 5.