If you need more help check this:
http://www.crankshaftcoalition.com/w...EI_distributor
From the bottom of the page additional informative links:
Resources
Spark plug cross-reference
Exploded view of an HEI distributor
Ported vs. manifold vacuum
GM HEI rebuild, install info
GM HEI distributor notes, etc.
Description of an HEI rebuild
Return to: Distributor shaft end play adjustment, above
HEI vacuum advance specs
GM points-type vacuum advance can specs and info (Lars)
Return to: Vacuum advance, above.
Crankshaft Coalition wiki articles:
Firing orders of various engines.
Several articles on valve adjustment
Carb vacuum port ID
How to install a distributor
Determining top dead center
How to find the number one cylinder in an engine
How to make a timing tape
Timing tabs and damper TDC lines SBC
Estimating timing chain wear
How to make a timing tape
Here is another accurate source of info:
http://www.hotrodhotline.com/md/html/ignition.php