Hi Seeburg. So glad to meet a responding Seeburg owner.
I am not familiar with your model number , though I think models ending with -11 or -12 can be "low boy" design. . I cannot find info on my model number, only built in 1973, much later than yours and with older designs of relays, and set up units, multipliers etc. see my name plate phtoto
My unit does not even go as far as yours. It will power up, light up, accept my nickels, allow me to pull the handle, than reset allowing more coins. No light telling me how many plays, pay out etc.
Our problems should be similar: the set up units, multiplier units, (Odd units, Line Unit), switches and relays of the coin relay pull in an dlock in, initial coin relay etc.
Do you have any experience fixing slot machines, or the manuals or schematics. I have no experience before, but find it very challenging. So I hope to continue.
Do share some photos.