I remember watching the brainstorming happening from way back when. It was quite awesome and full of thrift!
Thing would be considerably easier now. At that stage, I may be wrong, but it wasn't widely known what the correct number of teeth and pitch where on the gears. The gears where from spinning candy suckers if I recall correctly. Online ordering wasn't as easy as it is now either.
If I was to do this now, hopefully with access to the correct parts, I would
Use a kade instead of the dual strike hack.
Order the gears from mouser, mcmaster or some similar place.
Instead of using toys, would find a good image of a pistol grip and trace it on to card board until it was scaled correctly. A person could even use a power drill as better example. Then use that as a template to fashion out of plywood and route as necessary.
If you need help with pictures of the original, just ask. In regards to the materials in that tutorial, it wasn't for arcade use. It also wasn't designed by industry giants that access to engineers to make proto types. Chances are the first Atari proto-types where from pop guns with holes drilled in them and bolted on to ready rod. But I digress.
No to all the other questions.
BTW

: YEAR OF STAR WARS

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