Fun game. As for setting it up, make sure the plunge launches into the pops reliably.
The eject from the Bunker should hit the left flipper and be able to be stopped most of the time. It shouldn't trigger the left sling.
Make sure the diverter is not bound up or dragging on the ramp. The coil that moves it is pretty weak and if anything is gunked up it often doesn't work.
The T-Rex has its own set of problems: making sure the switches are set correctly, the wire for the coil that closes the mouth breaking, the link that moves the jaw breaks.
Make sure the game ROMs are updated to version 5.13 as this has a revision that helps keep the left right motor for the T-Rex from stripping the gears.
That's all I can think of now. Have fun!