The schematic is from the sample run. They were usually hand drawn at that stage until they finalized them and had them stenciled and printed.

Does your serial number have an S adjacent to it? It would be in all positions - top of head, green tag on arch, and below the coin door.

Usually more than 1, less than 100.

Depends on the title regarding desirable. Typically if a game has differences and it's a really popular title, it adds some value. But solid state sample games are much more desirable than EM sample games.

It's all relative. It may make them a little more valuable. But not by much usually.

The biggest contributor to value is condition. A worn sample game isn't worth much because it's worn. A clean non sample game is worth more because it is clean.

Thanks. I've been working on it for a while now.

One more thing. It's possible someone prior to you put a sample schematic with your non sample game. My suspicion is that the production games usually followed the sample games function/schematic wise. So you should have no issue following the circuits. It would not surprise me if they changed wire colors from sample to final in some items. But I don't really know.

Well if there is no S it probably isn't a sample game but the schematic is from one but could have been acquired and attached to the game somewhere along the line. It still could be a test game but you could verify that by checking for differences from regular production games. I would bet there are a few that ended up having no differences though so well...never mind! LOL