Firstly, on this age of boat the #1 concern is stringer rot. Do yourself a favor and search the forum for stringer rot, there's lots here. Others will disagree with me but in reality, it's only the stringers that sit under the motor that are must repair items. The boat will operate just fine with questionable stringers everywhere else.

Secondly, if there's a Ford 360 in there, it's not the original motor. It should be a 351W or a 454. If it truly is a 460 I'd walk away, lord knows what kind of bodging would have gone on if the owner just dropped an old Ford truck motor in there.

3500 could be a great deal or a total rip off depending on the condition of both the boat and trailer.

Getting back to your question, you need to tap the stringers under the motor to see if they sound solid(good) or hollow (bad). Stomp around the floor looking for soft spots, and if the floor is solid, find out if it's been replaced. If it has, ask if there are any pictures of the process.

Do a compression check on the motor or have someone who knows how to, do one for you.

Now, if you're a slalom guy, word is you will love this boat. It punched above it's weight when it was made, and even now it's a great slalom boat. That being said I've never skied behind one, my boat is a Rider. If you want to fill it with ballast and make big waves, move on, it's the wrong boat for that.

Are you saying you have a 5000 budget to buy and fix up, or 5000 to put into it after purchase?