My guess is just a typo that should have been “1”
John, If you’re referring to seal kits that say 18 HP and up, everything in them will work for your 15 except for the prop shaft seal. I think late ’57 and into ’58, 18 horse changed to a smaller O.D. seal that would be too small for the 15 prop head. That’s why I mentioned the guys who can make up a kit because I think for the most part the members who do that know what seal you’ll need with the ’53 15 HP.
The other options you have are buying the kit from ebay and also buy the the SKF 6280.
Or get the kit for the 18, and use that smaller seal with a reducer bushing. There is a member who used to make them and as of a couple months ago I thought he mentioned on here he still had a few. His name is Ben, OldJohnnyRude on YouTube and fisherman6 on here. Maybe he’ll see this and confirm whether he still has some.
