Never seen one of these in the flesh and would imagine a lot more electronics in there with the hold feature and I guess these machines were into the 1970s. I have lots of Aristocrat parts and guides, but none cover this machine, only basic hopper machines.
Have you pictures of your machine you are able to share?
I can see relays, transformers, lighting ballast, and if you unscrew the knurled knob holding down the lid with the fuse holders on the front I think you'll find a capacitor lurking. Depending on how active it all is and when it was last powered up the capacitor could still curl your teeth.