I have 3 sets of 2 lamp 4' T12 florescent lights in my kitchen.

Expect for one which I replaced last year I believe they have the
original ballasts.

My question is are the 2 blue wires and the 2 red wires interchangeable
between the ballast and the lamp holder clips?

IOW, there is no inner red/blue wires and no outer red/blue wires?

Just wondering because I know I just hooked up the blue and red wires (4
wires) on the other ballast that I replaced w/o "tracing" inner and
outer wires, because on the new ballast the 2 red wires are one on top
of the other and the 2 blue wires are side-by-side.

Reason I ask is because I had to replace another faulty one today and
the lights ran for about 2 minutes and then they went out.

I'm guessing it was just a faulty ballast. This is what I'm installing.

http://www.homedepot.com/p/GE-4-ft-1...7499/100632124