I'm going to use one of the HEI distributors from Langdon's on my engine rebuild. The recommended advance is somewhere around 20 degrees. The shop manual for the 235/261 says to use a timing light and get the flywheel ball to show up at the right time, but I'm thinking that is for a 5 degree advance.

How does one go about setting at 20 degrees for initial setup? Once I get it close enough to run I can just use one of those fancy timing lights to get exact.

Thanks in advance.

shoeless