Hello Folks. I am starting a few new projects next spring and need some Info/help. I have an 1970 C20 Chevy truck. with a Sm465 trans. and a gear venders OD. I plan on installing one of my 430ci. BBB probably a 1968 from an Electra i used to have. It is a 2 barrel carb. This does not have the large port heads. This will be my trailer pulling rig/ blacksmithing truck. I Plan on running Propane Pure vaper carb set up. NOT duel fuel.... I remember an old write up, I think in Carcraft of someone doing this on a Electra or Riv. I just can't remember if they needed to change the valve seats in the heads. Normally they use powdered metal or really high temp stainless valve for this. but since the Buicks run a high nickel content, I am not sure if it is needed. Also will i need to have the rotating assembly rebalanced for the stick trans? or can i just have the new flywheel balanced per the flex plate in the same location? Some help on these matters would be much welcomed. Thanks. BuickSmith.