*Edit, even better, check out the manual where Herg mentioned*
With the playfield up, find the board that is bad (each one has a number label printed on it). Also, look at whats plugged in, i'm at work right now, but if my memory serves me right, there is a plug with a red end, which is outgoing to the next board, and there is a green plug on the other side which is incoming from the previous board, and a power cable in the middle. So in my case, recently, #25 blew, while I waited for the new board (with the built in filter)
So i went to #24 (the good board b4 25) and unplugged the red outgoing side (which is going to #25), then i went to #25, and unplugged the outgoing red side (which is going to #26) and plugged it in to the now empty slot in #24.
So what I did was bypass the bad #25 (so #24 now goes next to #26)
Then you go into settings, I believe it is game settings, scroll down to the bottom where you see the numbered light boards, and in my case, i found #25, and turned it off.
Once I got the new board, i swapped it in, plugged the cables back in how they were, and turned #25 back on.