Hey Dustin did you get a manual with the game? As LTG said it sounds like a switch matrix issue if you are getting tilts for apparently no reason. If you have the manual great if not download one. You need to find the switch matrix chart, page 2-50 in the manual. It will be a grid with all the switches in rows and columns. Turn the game on and take the glass off. Find the tilt switch on the chart, now start a game and activate the switches in that row then in the column for the tilt. If you press on a target or activate a ramp switch and the game tilts this is the area you need to look at for backwards diodes or shorted wires etc. This should help you narrow it down.
Also what kind of tilt is it? Do you just lose the ball (plum bob tilt) or does the game end (slam tilt)? Will make a difference on which columns and rows you should be looking at.
If I find myself heading up to Chicago soon I might be able to stop by and lend a hand, but I bet you can figure it out. Check those switches. I had a TFTC game and every time I hit the ramp it would tilt. Someone put the diode on backwards for a ramp switch. Someone sold me my CFTBL with no diodes on the right flipper coil. It happens.
Good luck