Do I Need a Bushing for the TC for a 273/318 Swap?

@yellow rose Perhaps they were forged 273 or 318 poly cranks (2128278 2128869 2205700) balance drilled to 340 specs? PAW used to sell them that way. Is there a stamped number evident on those small register 340 cranks? 68 production year transmissions were also built from june 67 production dates and they all had larger registers for 68 model years. a 1 year only 67 LA 318 would have the small register too, it may even have a forged crank.