Eh don't feel too bad, I just went ahead and bought new big blues (or big blacks in this case) for all my Atari titles as well. I've just gotten into the habit of recapping everything since these games are so old.
I had a Centipede that I wanted to put the multipede kit into which runs on a millipede board. The centipede worked great and the millipede board/kit worked great on my test bench. When the millipede board was installed in the centipede cab with the adapter, I got garbage on the screen.....but worked fien with the centipede board. Long story short, it was the big blue. Ever since then, I replace them in all my atari machines when I get them.