Just got an Upper Deck, wiring has some serious sins but this seems basic. There are 2 AC power plugs in the back box and I don't see anywhere to plug them in?

Yes I believe the game is complete unless there was supposed to be a power strip to plug the AC plugs into. I just got the machine and I'm still learning about it. I'd also like to know how many balls are supposed to be in the machine, more than 1?
I was reading a post yesterday about audio boards and someone suggesting that upper deck had the same board as another game, I looked at the schematic for the machine and it does not match the pinouts of the schematic that was posted. I'll dig a little deeper if that is what you are after?

Sorry, I was wrong. I just had a look at the sound module, the schematic shows an interface to a sound module but the module consists of 4 boards so the schematic I saw was probably the correct one. Do you have a specific question about the board?

I solved my original problem, rookie mistake, I hadn't fished all of the cables up to the back box, this game is much harder to fish the cables compared to a regular pinball.