I remember these games. We had two of them at the Gold Mine arcade in the Capital Mall here in Olympia, Washington back in the 1970s. I am an expert in 16mm film projectors. I was fascinated by these machines and one day I asked the attendant at the Gold Mine if I could see the projectors inside the machine. The first machine had two RCA 1600 projectors inside. They were constantly breaking down. About three months later, this particular machine was replaced with a different Wild Guman that had different projectors in it. I asked to look at the projectors in it. This machine had two Eiki "R" series projectors which were retrofitted with "changeover" systems to douse the light from either projector depending on what the player did.
I can only theorise that Nintendo/Sega installed the RCA 1600 projectors for machines used in North American markets because RCA was a long-established 16mm projector maker of reliable 16mm projectors. While that was certainly true of their famous "400" series projectors, that was not the case with the 1600 projector. I've nominated it as the WORST 16mm projector ever built. The RCA engineers must have been out to lunch when this machine was designed. The two major problems were the forward/reverse clutch assembly and the amplifier for the film's sound. I assume operator complaints about the RCA projector problems caused Nintendo/Sega to switch projector brands to that USA newcomer (at the time) to Eiki. Eiki was based in Japan and was very popular in asian countries. Eiki was making significant sales to school districts all over the USA and was starting to overtake Bell & Howell in projector sales. Plus Eiki was establishing many local projector distributors and repair facilities. The Eiki projector was superior to the RCA 1600 and much more reliable.
RCA soon shed their company of all 16mm projector manufacturing and sold the model 1600 rights, tooling, and inventory to their competitor, Viewlex. Viewlex engineers went to work right away on fixing RCA's fuckups. They redesigned the forward/reverse clutch assembly and completely redesigned the amplifier. These two major improvements made the 1600 projector a reliable projector, but too late for Wild Gunman.