The wire on the right is what Toyota referred to as an 'exciter' wire. It was designed to 'steal' 12 volts from the starter and boost the coil during startup. IIRC, it was used from 73 to 78 and then abandoned.
For years you could get the starter either with or without the extra wire. IMO, if you didn't have an ignitor, you didn't need one.
Now Toyota has superceded all early starters to the gear reduction model, which does not have the provision. Technically, this is a violation of emissions rules, since it will modify the spark profile, but the BAR is clueless.