Hey Luzur, glad someone with talent is doing this!
If this does go into production please be as accurate with the plastic sizes and shapes as possible. Make sure to include the holes for the screws as well. There also needs to be a bit of a margin between the art and the edge of the plastic too. The art cannot go right up to the edge as it looks like you have it now. It will need a strong outline too. I also would even suggest making a copy of each piece, cut it out and then see how they fit on your machine.
I will see if I can get a paper print out of the layout I did for the original plastics as a guide. I think that would be helpful.
As far as finishing the art for production goes... Someone else would need to comment on that. I imagine your line art would need to be traced so it's nice and solid and the colors are strong and consistent as well. Are you going to "finish" these on a computer?
Creatively, I suggest that you keep it as close to Paul Faris style as possible. I would try to avoid any specific "custom" elements not copied from his work. (As in, don't draw your version of a mandril but closely copy one of his) I think even looking at some other machines he did would be helpful for adding different elements not found on GL that would work with the theme. For example, the skulls from Paragon.
The games that Paul Faris did around that time with that sort of style are: Centaur, Paragon, Lost World, Andromeda and maybe Space Invaders. After those, the runners up that *might* have useful elements are Hook and Frankenstein.
And, again, I think it would be a good idea if some could send Luzur better photos of those prototype plastics pictured above.
I have a bit of experience with all this but I'm far from an expert and encourage interested parties (people who would actually want a set) to chime in as to what would do this special set of plastics justice and to make them desirable to us GL owners.
Personally, something I would like to see is some type of a symmetrical element added to the sling plastics like a skull or weapon.
Please chime in GL peeps!