Re: 1964 Penn Yan 16' Fibreglass
Welcome! She looks great for a 46 year old... better than most. A fine little ship.
How do you plan to use her? Ski, fish, or just cruise the lake? At the heart, a 60 hp on a 16' is going to limit your hole shot and top end. It's just not a fast setup. Plus the hull design is not cutting edge, though I bet she cuts a fine wake.
If the motor isn't performing at 100%, maybe a carb rebuild is just the ticket. You might be right on the money doubting the high speed jets.
You might also consider looking at the prop.
Good luck!