just bought this car couple weeks ago smoked some on start up has benn sitting 16yrs started tearing it apart to do valve guide seals . the seals are there just hard as hard plastic went to local parts store and got fel pro seals #ss 10058 box says for 305 350 429 engines 1965 to 1979 looks like little umbrellas directions say push seal down on seal body until it touchs top of valve stem guide or boss the seal will find its proper position on the stem once the engine starts. ok is the boss the bottom of the valve i hope so just did one side 2 day

 

I would recommend going w/ the stock valve seals that are square O-rings that go below the keepers. Umbrella seals tend to keep the valve guides too dry.