Re: '64 evinrude 18hp
David, do yourself a big favor and get a parts book for your motor. You would be surprised at how much stuff is available from your local Evinrude dealer. However, unless you go in with the part number, most of them won't give you the time of day. It's surprising how their attitude changes when all they have to do is pull the part off the shelf and collect your money.
Also, a great many parts are the same for your motor as the '68 on
http://shop.evinrude.com/ But unless you have the part number for yours, you have nothing to compare. It's great to be able to buy stuff direct from Evinrude. Saving gas offsets the postage, and no B.S. has to be taken.