Tell-tale Signs That Engine Has Been Worked On?

[KRAM36]

First thing, I admit I did zero background checking into Boxster issues. I've just never heard of Porsche reliability problems, so I figured I was safe as long as the car didn't break during a very rigorous test drive.

Anyways the 2003 Box S I bought has 98k miles on it. I've had it for 3 weeks now and no issues that I know of, but after reading all these IMS problems I'm kinda of hoping this car has had that issue addressed previously. The car came with no maintenance records. Is there any way for me to tell of engine work being done.

Thanks