Ok then, I will give you the title of this service manual but it has been out of print for 28 years so I am not sure the odds on finding another one.

Outboard Motor Service manual

(9th Edition - Volume1)

Covers Motors below 30 Horsepower

Published by ABOS Marine Publication Division

Intertec Publishing Corp.

P.O. Box 12901, Overland park, Kansas 66212

Copyright 1983

Lets see covers from 1974 to 1982 Evinrude 9.9 and 15 hp models

in 1979 the model numbers on the 15 hp Evinrude were 15904, 15905, *15954, and *15955

The two numbers with the Astrix (*) are electric start models.

Hmmm... Have to find a better way to type this stuff, there are 8 pages of diagrams and information.