I've got a World Sport too,Sept-83 build date.The 40.5 wheelbase gives a nice ride.I've got stem shifter and almost no braze-ons, just cable stops.As above,i'd just replace,regrease, & clean the beast.I guess '84 went with the seat tube's,slightly bolder decals.This weekend Ebuy had an mint '84 W'Sport NOS,50$.I had a '75 Le Tour too,they're great bikes for novice mechanics.