Don't know if 74 runner would be the same but here goes. #1 20 Amp=Brk. warning lt. w/lift safty relay, interlock control,deck lid rel sol, &the following std, cluster items, oil pres lt .V/limiter, fuel & temp Gauge...2=20 amp Clock feed (std cluster) Horn (dual) , Horn relay & key buzzer, seat belt lt. and buzzer,. 3= 20 amp Stop, trunk,dome & aft. dome lts. & hazard flashers. 4 20 amp =Open door indicator lt. (taxi, ign.,map,tail,lics.,s/mrk., glove box & park lights,inst. lts, 5 = 5 amp. Cluster gear sel, ash rec, radio htr or a/c &acc sw. lts, also lighter,ign switch lt.time delay relay 6= 20 amp r. defog, a/c clutch, speed cont, & the following rallye cluster items,fuel,oil & temp guages,Feed & V/Limiter...7 = 20 amp htr. or a/c blower, and 8 = 20 amp b/up & rev gear indc lts. t/sigs & Radio, maybe this helps.