Not sure if you are still looking.. I have a Jacobs Pro Street Energy Pak on my '68 Fastback, but have no install manual. The P/N of the unit is 826-72-180 .
I wanted to add a tach to the Mustang, and looked for the manual a few months back. Sent an e-mail to Accel, and they indicated that they no longer provide Jacobs information.
If you have the same P/N, and are located in East Dallas, send me a PM. You can look at my install if that helps.