[husker boxster]

There's a lot to unpack in your post. I'll give you my opinions at a high level and others can chime in with more details / technical data.

First off, it's generally a recipe for disaster for someone to buy a Porsche on a limited budget with the idea of owning a Porsche on the cheap. While the car has depreciated, parts still have the Porsche tax associated with them. In general, there are no cheap Porsches. Nice rollers (that only need engines) are usually $3-4K depending on year, condition, miles, options, etc. If you find one for $2500, chances are it needs more than just an engine swap. And you're talking about cars that are 20 yrs old, so generally it's going to need something replaced because of age. Bottom line is there are no cheap Porsches.

Porsches are not a 55 Chevy or a 67 Camaro that you can rip out whatever engine's in it and drop in an LS, connect a few wires, and blast off to your nearest C&C. Porsches have various electronic iterations, with each newer versions having more complicated electronics. Trying to put a newer engine into an older car will not work unless you commit to a massive rewiring project. I mention this because you want to put a 3.2 engine into a base Box. This means you'll need to buy at least a 2000 base because that was the 1st yr of the S. 97-99 will have different electronics.

I'm not saying it's impossible to do what you want to do, but you're not going to do it on the cheap. For $8500 you could probably find an S that needs some of the basic fixes (window regulators, old suspension, AOS, etc) that would be great for a shade tree mechanic to work on.

I'll leave you with this: it's not rocket science but it's not simple math either. If you're looking to get into Porsche ownership on the cheap, just find one that needs some basic maintenance and buy it. If you're looking for a project to keep you out of the bar for a few yrs, knock yourself out.