Intake manifold SB
LOL, That engine had been stomped on alot allready due to the 2bbl delivering poor acceration abilty with it being under carbed to begin with. ;)
IMO, look in the 4-sale section for a LD4B, Performer or Weiamds Action Plusintake for a much better performing intake and ports that are closer in size to your current heads.
Leave the other 2 alone unless your going to really step up the program in a big way.