Re: Can this swap be done?
Even if the Bayliner is in pristine shape (very unlikely) and used the same drive, I wouldn't consider such a swap, unless your 4winns hull is toast, and your engine/drive is in excellent condition. Sell the 4winns and look for a complete package.
PS: It is highly likely the Bayliner hull/floor/transom/stringer are toast, if this is of the vintage that would have used your drive. The seller either reused the engine/drive package or parted it out, and is looking at a low cost option instead od hauling to landfill. Be very careful with your inspection.