After deliberating I decided to drill out the 2 top rivets closest to the back and punch the carriage bolts into the machine. That allowed the needed play to slightly pry the back up and outwards, allowing the bonnet to release and removal of both. I took a few pics of the process and that now begs a few questions.
In one picture you can see rust and a bare wire. I feel sure a battery discharged acid. Perhapse a battery that opened a solenoid that rang a bell and opened the center door for the jackpot payout?
I also have my mills lock out and the serial # pressed into it. Will I now be able to have a key cut based on the lock number?
I was able to clean all glass and I found close to a 100 nickels most in the 50ies but a few from 1949 and the main tube is full of coins but I dont know how to get into that just yet.
Thanks everyone for the guidance.