How to tell the difference between a 3sfe and 5sfe? Options

[6strngs]

Hey, I'm likely going to be buying a celica in the next week or so, but one concern I have with it is that the motor was replaced with a "30,000 mile" motor. I know from when I was trying to find an engine for the celica I used to have, that most places just sold a 3sfe instead of the 5sfe, so I was wondering if there was any way I could tell if this car I'm buying has a 3s or 5s? It's got the 5s intake manifold and valve cover for sure, but I figure those could just be bolted onto a 3s. Is there any other sure-fire way to tell which engine it's got? Thanks in advance

[6strngs]

That's what I was thinking but I think the 5s manifold and valve cover bolt to the 3s, so if someone were just swapping the long block they could've just re-used the 5s stuff. I can't recall ever seeing a block identification number or vin number anywhere on the block last time I had a 5s out of the car, but that was several years ago.