WD-40 will gum in time and make it sticker. My Master (to use Roland's terminology) made me throw it away - Kroil, penetrating oil and light machine oil has replaced it. I'd take the distributor apart, clean it and lubricate it with light oil or engine oil, except fort he lobes - there one should use Bosch distributor grease sparingly. Early_S_Man will likely have the vacuum and other specs.
JIM